diff --git a/codegen-superclass-test/.gitignore b/codegen-superclass-test/.gitignore
new file mode 100644
index 0000000..cbaaccb
--- /dev/null
+++ b/codegen-superclass-test/.gitignore
@@ -0,0 +1,19 @@
+/.classpath
+/.gradle/
+/.project
+/.settings/
+/bin/
+/build/
+/target/
+/.metadata
+/.idea/
+.factorypath
+/.claude/
+/data/
+/.apt_generated/
+
+/src/main/java/codegen
+/src/main/kotlin/codegen
+/src/main/resources/META-INF/codegen
+/src/test/java/codegen
+/src/test/kotlin/codegen
diff --git a/codegen-superclass-test/build.gradle.kts b/codegen-superclass-test/build.gradle.kts
new file mode 100644
index 0000000..1ce7ed5
--- /dev/null
+++ b/codegen-superclass-test/build.gradle.kts
@@ -0,0 +1,97 @@
+plugins {
+    java
+    alias(libs.plugins.doma.compile)
+    id("org.domaframework.doma.codegen")
+}
+
+java {
+    toolchain.languageVersion.set(JavaLanguageVersion.of(17))
+}
+
+repositories {
+    mavenLocal()
+    mavenCentral()
+}
+
+dependencies {
+    implementation(libs.doma.core)
+    annotationProcessor(libs.doma.processor)
+
+    testImplementation(platform(libs.junit.bom))
+    testImplementation(libs.junit.jupiter.api)
+    testRuntimeOnly(libs.junit.jupiter.engine)
+    testRuntimeOnly(libs.junit.platform.launcher)
+
+    testImplementation(libs.h2)
+
+    domaCodeGen(libs.h2)
+    // Add compiled classes to domaCodeGen classpath for superclass resolution
+    domaCodeGen(sourceSets.main.get().output)
+}
+
+val initScript = file("init_h2.sql")
+val _url = "jdbc:h2:mem:superclass_test;INIT=RUNSCRIPT FROM 'file:${initScript.absolutePath}'"
+val _user = ""
+val _password = ""
+
+domaCodeGen {
+    register("superclass") {
+        val basePackage = "codegen"
+        url = _url
+        user = _user
+        password = _password
+        schemaName = "PUBLIC"
+        entity {
+            packageName = "${basePackage}.entity"
+            // Use AbstractEntity as superclass
+            superclassName = "base.AbstractEntity"
+            // Use AbstractEntityListener as listener superclass
+            listenerSuperclassName = "base.AbstractEntityListener"
+        }
+        dao {
+            packageName = "${basePackage}.dao"
+        }
+    }
+}
+
+tasks {
+    // Step 1: Create a task to compile only base classes first
+    val compileBaseClasses = register<JavaCompile>("compileBaseClasses") {
+        source = fileTree("src/main/java") {
+            include("**/base/**")
+        }
+        classpath = configurations.compileClasspath.get()
+        destinationDirectory.set(layout.buildDirectory.dir("classes/java/main"))
+    }
+
+    // Step 2: domaCodeGen depends on base classes being compiled
+    matching { it.name.startsWith("domaCodeGen") }.configureEach {
+        dependsOn(compileBaseClasses)
+    }
+
+    // Step 3: Full compilation depends on code generation
+    compileJava {
+        dependsOn("domaCodeGenSuperclassAll")
+    }
+
+    test {
+        useJUnitPlatform()
+    }
+
+    val deleteSrc = register("deleteSrc") {
+        doLast {
+            // Delete only generated code, not base classes
+            delete("src/main/java/codegen")
+            delete("src/main/kotlin/codegen")
+            delete("src/main/resources/META-INF/codegen")
+            delete("src/test/java/codegen")
+            delete("src/test/kotlin/codegen")
+        }
+    }
+
+    clean {
+        dependsOn(deleteSrc)
+    }
+}
+
+
diff --git a/codegen-superclass-test/init_h2.sql b/codegen-superclass-test/init_h2.sql
new file mode 100644
index 0000000..192c78a
--- /dev/null
+++ b/codegen-superclass-test/init_h2.sql
@@ -0,0 +1,52 @@
+-- Create test tables with superclass fields
+
+CREATE TABLE EMPLOYEE (
+    ID BIGINT PRIMARY KEY AUTO_INCREMENT,
+    NAME VARCHAR(100) NOT NULL,
+    EMAIL VARCHAR(100),
+    DEPARTMENT VARCHAR(50),
+    SALARY DECIMAL(10, 2),
+    -- Superclass fields
+    CREATED_BY VARCHAR(50),
+    CREATED_AT TIMESTAMP,
+    UPDATED_BY VARCHAR(50),
+    UPDATED_AT TIMESTAMP,
+    DELETED BOOLEAN DEFAULT FALSE
+);
+
+CREATE TABLE DEPARTMENT (
+    ID BIGINT PRIMARY KEY AUTO_INCREMENT,
+    DEPT_NAME VARCHAR(100) NOT NULL,
+    LOCATION VARCHAR(100),
+    -- Superclass fields
+    CREATED_BY VARCHAR(50),
+    CREATED_AT TIMESTAMP,
+    UPDATED_BY VARCHAR(50),
+    UPDATED_AT TIMESTAMP,
+    DELETED BOOLEAN DEFAULT FALSE
+);
+
+CREATE TABLE PROJECT (
+    ID BIGINT PRIMARY KEY AUTO_INCREMENT,
+    PROJECT_NAME VARCHAR(200) NOT NULL,
+    START_DATE DATE,
+    END_DATE DATE,
+    BUDGET DECIMAL(15, 2),
+    -- Superclass fields
+    CREATED_BY VARCHAR(50),
+    CREATED_AT TIMESTAMP,
+    UPDATED_BY VARCHAR(50),
+    UPDATED_AT TIMESTAMP,
+    DELETED BOOLEAN DEFAULT FALSE
+);
+
+-- Insert sample data
+INSERT INTO EMPLOYEE (NAME, EMAIL, DEPARTMENT, SALARY, CREATED_BY, CREATED_AT, UPDATED_BY, UPDATED_AT, DELETED)
+VALUES ('John Doe', 'john@example.com', 'Engineering', 75000.00, 'admin', CURRENT_TIMESTAMP, 'admin', CURRENT_TIMESTAMP, FALSE);
+
+INSERT INTO DEPARTMENT (DEPT_NAME, LOCATION, CREATED_BY, CREATED_AT, UPDATED_BY, UPDATED_AT, DELETED)
+VALUES ('Engineering', 'Building A', 'admin', CURRENT_TIMESTAMP, 'admin', CURRENT_TIMESTAMP, FALSE);
+
+INSERT INTO PROJECT (PROJECT_NAME, START_DATE, END_DATE, BUDGET, CREATED_BY, CREATED_AT, UPDATED_BY, UPDATED_AT, DELETED)
+VALUES ('Project Alpha', '2026-01-01', '2026-12-31', 500000.00, 'admin', CURRENT_TIMESTAMP, 'admin', CURRENT_TIMESTAMP, FALSE);
+
diff --git a/codegen-superclass-test/src/main/java/base/AbstractEntity.java b/codegen-superclass-test/src/main/java/base/AbstractEntity.java
new file mode 100644
index 0000000..77d13e2
--- /dev/null
+++ b/codegen-superclass-test/src/main/java/base/AbstractEntity.java
@@ -0,0 +1,72 @@
+package base;
+
+import java.io.Serializable;
+import java.time.LocalDateTime;
+import org.seasar.doma.Column;
+
+/**
+ * Base entity class with common audit fields.
+ * This class demonstrates superclass functionality in Doma CodeGen.
+ */
+public abstract class AbstractEntity implements Serializable {
+
+    /** Created by user ID */
+    @Column(name = "CREATED_BY")
+    private String createdBy;
+
+    /** Created timestamp */
+    @Column(name = "CREATED_AT")
+    private LocalDateTime createdAt;
+
+    /** Last updated by user ID */
+    @Column(name = "UPDATED_BY")
+    private String updatedBy;
+
+    /** Last updated timestamp */
+    @Column(name = "UPDATED_AT")
+    private LocalDateTime updatedAt;
+
+    /** Logical delete flag */
+    @Column(name = "DELETED")
+    private Boolean deleted;
+
+    public String getCreatedBy() {
+        return createdBy;
+    }
+
+    public void setCreatedBy(String createdBy) {
+        this.createdBy = createdBy;
+    }
+
+    public LocalDateTime getCreatedAt() {
+        return createdAt;
+    }
+
+    public void setCreatedAt(LocalDateTime createdAt) {
+        this.createdAt = createdAt;
+    }
+
+    public String getUpdatedBy() {
+        return updatedBy;
+    }
+
+    public void setUpdatedBy(String updatedBy) {
+        this.updatedBy = updatedBy;
+    }
+
+    public LocalDateTime getUpdatedAt() {
+        return updatedAt;
+    }
+
+    public void setUpdatedAt(LocalDateTime updatedAt) {
+        this.updatedAt = updatedAt;
+    }
+
+    public Boolean getDeleted() {
+        return deleted;
+    }
+
+    public void setDeleted(Boolean deleted) {
+        this.deleted = deleted;
+    }
+}
diff --git a/codegen-superclass-test/src/main/java/base/AbstractEntityListener.java b/codegen-superclass-test/src/main/java/base/AbstractEntityListener.java
new file mode 100644
index 0000000..cc45c97
--- /dev/null
+++ b/codegen-superclass-test/src/main/java/base/AbstractEntityListener.java
@@ -0,0 +1,32 @@
+package base;
+
+import java.time.LocalDateTime;
+import org.seasar.doma.jdbc.entity.EntityListener;
+import org.seasar.doma.jdbc.entity.PreInsertContext;
+import org.seasar.doma.jdbc.entity.PreUpdateContext;
+
+/**
+ * Base entity listener that automatically sets audit fields.
+ */
+public class AbstractEntityListener<E extends AbstractEntity> implements EntityListener<E> {
+
+    @Override
+    public void preInsert(E entity, PreInsertContext<E> context) {
+        LocalDateTime now = LocalDateTime.now();
+        entity.setCreatedAt(now);
+        entity.setUpdatedAt(now);
+        entity.setCreatedBy("system");
+        entity.setUpdatedBy("system");
+        if (entity.getDeleted() == null) {
+            entity.setDeleted(false);
+        }
+    }
+
+    @Override
+    public void preUpdate(E entity, PreUpdateContext<E> context) {
+        entity.setUpdatedAt(LocalDateTime.now());
+        entity.setUpdatedBy("system");
+    }
+}
+
+
diff --git a/codegen/src/main/java/org/seasar/doma/gradle/codegen/CodeGenPlugin.java b/codegen/src/main/java/org/seasar/doma/gradle/codegen/CodeGenPlugin.java
index 00fb1b4..5766c32 100644
--- a/codegen/src/main/java/org/seasar/doma/gradle/codegen/CodeGenPlugin.java
+++ b/codegen/src/main/java/org/seasar/doma/gradle/codegen/CodeGenPlugin.java
@@ -188,6 +188,7 @@ private void connectProperties(CodeGenEntityDescTask task, CodeGenConfig extensi
     task.getVersionColumnNamePattern().set(extension.getVersionColumnNamePattern());
     task.getLanguageClassResolver().set(extension.getLanguageClassResolver());
     task.setEntityConfig(extension.getEntityConfig());
+    task.setCodeGenClassLoaderProvider(extension.getClassLoaderProvider());
   }
 
   private void connectProperties(CodeGenEntityTask task, CodeGenConfig extension) {
diff --git a/codegen/src/main/java/org/seasar/doma/gradle/codegen/extension/CodeGenConfig.java b/codegen/src/main/java/org/seasar/doma/gradle/codegen/extension/CodeGenConfig.java
index a5cf109..c778a52 100644
--- a/codegen/src/main/java/org/seasar/doma/gradle/codegen/extension/CodeGenConfig.java
+++ b/codegen/src/main/java/org/seasar/doma/gradle/codegen/extension/CodeGenConfig.java
@@ -38,6 +38,8 @@ public class CodeGenConfig {
 
   private final String name;
 
+  private final Project project;
+
   private final Configuration configuration;
 
   private final Property<GlobalFactory> globalFactory;
@@ -93,6 +95,7 @@ public class CodeGenConfig {
   @Inject
   public CodeGenConfig(String name, Project project) {
     this.name = name;
+    this.project = project;
 
     this.configuration = project.getConfigurations().getByName(CONFIGURATION_NAME);
 
@@ -473,4 +476,21 @@ public void sql(Action<SqlConfig> action) {
   public void sqlTest(Action<SqlTestConfig> action) {
     action.execute(sqlTestConfig);
   }
+
+  /**
+   * Returns a Provider that creates a ClassLoader including the domaCodeGen configuration classpath.
+   * This can be used by tasks to load classes specified in entity configuration.
+   *
+   * <p>The ClassLoader is created lazily when the Provider is resolved (during task execution),
+   * ensuring that all dependencies in the domaCodeGen configuration are properly resolved.
+   *
+   * <p>Note: If the domaCodeGen configuration is empty or null, the class's own ClassLoader is returned.
+   * Otherwise, each call to {@code get()} creates a new URLClassLoader instance. In the latter case,
+   * the caller is responsible for managing the lifecycle of the returned ClassLoader.
+   *
+   * @return a Provider that creates a ClassLoader including the domaCodeGen configuration classpath
+   */
+  public Provider<ClassLoader> getClassLoaderProvider() {
+    return project.provider(this::createClassLoader);
+  }
 }
diff --git a/codegen/src/main/java/org/seasar/doma/gradle/codegen/task/CodeGenEntityDescTask.java b/codegen/src/main/java/org/seasar/doma/gradle/codegen/task/CodeGenEntityDescTask.java
index 51dea53..8c2df7e 100644
--- a/codegen/src/main/java/org/seasar/doma/gradle/codegen/task/CodeGenEntityDescTask.java
+++ b/codegen/src/main/java/org/seasar/doma/gradle/codegen/task/CodeGenEntityDescTask.java
@@ -55,6 +55,8 @@ public class CodeGenEntityDescTask extends DefaultTask {
   private final Property<LanguageClassResolver> languageClassResolver =
       getProject().getObjects().property(LanguageClassResolver.class);
 
+  private Provider<ClassLoader> codeGenClassLoaderProvider;
+
   private EntityConfig entityConfig;
 
   @Internal
@@ -121,6 +123,15 @@ public void setEntityConfig(EntityConfig entityConfig) {
     this.entityConfig = entityConfig;
   }
 
+  @Internal
+  public Provider<ClassLoader> getCodeGenClassLoaderProvider() {
+    return codeGenClassLoaderProvider;
+  }
+
+  public void setCodeGenClassLoaderProvider(Provider<ClassLoader> codeGenClassLoaderProvider) {
+    this.codeGenClassLoaderProvider = codeGenClassLoaderProvider;
+  }
+
   @TaskAction
   public void create() {
     EntityPropertyClassNameResolver entityPropertyClassNameResolver =
@@ -165,7 +176,10 @@ private EntityDescFactory createEntityDescFactory(
       EntityPropertyDescFactory entityPropertyDescFactory) {
     Class<?> superclass = null;
     if (entityConfig.getSuperclassName().isPresent()) {
-      superclass = ClassUtil.forName(entityConfig.getSuperclassName().get(), "superclassName");
+      ClassLoader classLoader = codeGenClassLoaderProvider != null && codeGenClassLoaderProvider.isPresent()
+          ? codeGenClassLoaderProvider.get()
+          : getClass().getClassLoader();
+      superclass = ClassUtil.forName(entityConfig.getSuperclassName().get(), "superclassName", classLoader);
     }
     return globalFactory
         .get()
diff --git a/settings.gradle.kts b/settings.gradle.kts
index 40f2f69..9c3f2fe 100644
--- a/settings.gradle.kts
+++ b/settings.gradle.kts
@@ -11,4 +11,5 @@ if (releaseVersion != null) {
     include("codegen-h2-test")
     include("codegen-tc-test")
     include("codegen-template-test")
+    include("codegen-superclass-test")
 }