diff --git a/spring-core/src/main/java/org/springframework/core/CoroutinesUtils.java b/spring-core/src/main/java/org/springframework/core/CoroutinesUtils.java
index 8ad247f15c38..24198014dac4 100644
--- a/spring-core/src/main/java/org/springframework/core/CoroutinesUtils.java
+++ b/spring-core/src/main/java/org/springframework/core/CoroutinesUtils.java
@@ -130,7 +130,9 @@ public static Publisher<?> invokeSuspendingFunction(
 									KType type = parameter.getType();
 									if (!(type.isMarkedNullable() && arg == null) && type.getClassifier() instanceof KClass<?> kClass
 											&& KotlinDetector.isInlineClass(JvmClassMappingKt.getJavaClass(kClass))) {
-										arg = KClasses.getPrimaryConstructor(kClass).call(arg);
+										KFunction<?> valueClassConstructor = KClasses.getPrimaryConstructor(kClass);
+										KCallablesJvm.setAccessible(valueClassConstructor, true);
+										arg = valueClassConstructor.call(arg);
 									}
 									argMap.put(parameter, arg);
 								}
diff --git a/spring-core/src/test/kotlin/org/springframework/core/CoroutinesUtilsTests.kt b/spring-core/src/test/kotlin/org/springframework/core/CoroutinesUtilsTests.kt
index 86a12075be46..6aee679df09f 100644
--- a/spring-core/src/test/kotlin/org/springframework/core/CoroutinesUtilsTests.kt
+++ b/spring-core/src/test/kotlin/org/springframework/core/CoroutinesUtilsTests.kt
@@ -28,6 +28,8 @@ import reactor.core.publisher.Mono
 import reactor.test.StepVerifier
 import kotlin.coroutines.Continuation
 import kotlin.coroutines.coroutineContext
+import kotlin.reflect.full.primaryConstructor
+import kotlin.reflect.jvm.isAccessible
 
 /**
  * Kotlin tests for [CoroutinesUtils].
@@ -206,6 +208,15 @@ class CoroutinesUtilsTests {
 		}
 	}
 
+	@Test
+	fun invokeSuspendingFunctionWithValueClassWithPrivateConstructorParameter() {
+		val method = CoroutinesUtilsTests::class.java.declaredMethods.first { it.name.startsWith("suspendingFunctionWithValueClassWithPrivateConstructor") }
+		val mono = CoroutinesUtils.invokeSuspendingFunction(method, this, "foo", null) as Mono
+		runBlocking {
+			Assertions.assertThat(mono.awaitSingleOrNull()).isEqualTo("foo")
+		}
+	}
+
 	@Test
 	fun invokeSuspendingFunctionWithExtension() {
 		val method = CoroutinesUtilsTests::class.java.getDeclaredMethod("suspendingFunctionWithExtension",
@@ -293,6 +304,11 @@ class CoroutinesUtilsTests {
 		return value?.value
 	}
 
+	suspend fun suspendingFunctionWithValueClassWithPrivateConstructor(value: ValueClassWithPrivateConstructor): String? {
+		delay(1)
+		return value.value
+	}
+
 	suspend fun CustomException.suspendingFunctionWithExtension(): String {
 		delay(1)
 		return "${this.message}"
@@ -331,6 +347,13 @@ class CoroutinesUtilsTests {
 		 }
 	}
 
+	@JvmInline
+	value class ValueClassWithPrivateConstructor private constructor(val value: String) {
+		companion object {
+			fun from(value: String) = ValueClassWithPrivateConstructor(value)
+		}
+	}
+
 	class CustomException(message: String) : Throwable(message)
 
 }
diff --git a/spring-web/src/main/java/org/springframework/web/method/support/InvocableHandlerMethod.java b/spring-web/src/main/java/org/springframework/web/method/support/InvocableHandlerMethod.java
index 40c8414079ba..214d18e0faa1 100644
--- a/spring-web/src/main/java/org/springframework/web/method/support/InvocableHandlerMethod.java
+++ b/spring-web/src/main/java/org/springframework/web/method/support/InvocableHandlerMethod.java
@@ -319,7 +319,9 @@ public static Object invokeFunction(Method method, Object target, Object[] args)
 							KType type = parameter.getType();
 							if (!(type.isMarkedNullable() && arg == null) && type.getClassifier() instanceof KClass<?> kClass
 									&& KotlinDetector.isInlineClass(JvmClassMappingKt.getJavaClass(kClass))) {
-								arg = KClasses.getPrimaryConstructor(kClass).call(arg);
+								KFunction<?> valueClassConstructor = KClasses.getPrimaryConstructor(kClass);
+								KCallablesJvm.setAccessible(valueClassConstructor, true);
+								arg = valueClassConstructor.call(arg);
 							}
 							argMap.put(parameter, arg);
 						}
diff --git a/spring-web/src/test/kotlin/org/springframework/web/method/support/InvocableHandlerMethodKotlinTests.kt b/spring-web/src/test/kotlin/org/springframework/web/method/support/InvocableHandlerMethodKotlinTests.kt
index 513437eee696..82cac5450d70 100644
--- a/spring-web/src/test/kotlin/org/springframework/web/method/support/InvocableHandlerMethodKotlinTests.kt
+++ b/spring-web/src/test/kotlin/org/springframework/web/method/support/InvocableHandlerMethodKotlinTests.kt
@@ -112,6 +112,13 @@ class InvocableHandlerMethodKotlinTests {
 		Assertions.assertThat(value).isNull()
 	}
 
+	@Test
+	fun valueClassWithPrivateConstructor() {
+		composite.addResolver(StubArgumentResolver(Char::class.java, 'a'))
+		val value = getInvocable(ValueClassHandler::class.java, Char::class.java).invokeForRequest(request, null)
+		Assertions.assertThat(value).isEqualTo('a')
+	}
+
 	@Test
 	fun propertyAccessor() {
 		val value = getInvocable(PropertyAccessorHandler::class.java).invokeForRequest(request, null)
@@ -191,6 +198,8 @@ class InvocableHandlerMethodKotlinTests {
 		fun valueClassWithNullable(limit: LongValueClass?) =
 			limit?.value
 
+		fun valueClassWithPrivateConstructor(limit: ValueClassWithPrivateConstructor) =
+			limit.value
 	}
 
 	private class PropertyAccessorHandler {
@@ -238,6 +247,13 @@ class InvocableHandlerMethodKotlinTests {
 		}
 	}
 
+	@JvmInline
+	value class ValueClassWithPrivateConstructor private constructor(val value: Char) {
+		companion object {
+			fun from(value: Char) = ValueClassWithPrivateConstructor(value)
+		}
+	}
+
 	class CustomException(message: String) : Throwable(message)
 
 }
diff --git a/spring-webflux/src/main/java/org/springframework/web/reactive/result/method/InvocableHandlerMethod.java b/spring-webflux/src/main/java/org/springframework/web/reactive/result/method/InvocableHandlerMethod.java
index 89fd48c2f599..57c32db1a181 100644
--- a/spring-webflux/src/main/java/org/springframework/web/reactive/result/method/InvocableHandlerMethod.java
+++ b/spring-webflux/src/main/java/org/springframework/web/reactive/result/method/InvocableHandlerMethod.java
@@ -332,7 +332,9 @@ public static Object invokeFunction(Method method, Object target, Object[] args,
 								KType type = parameter.getType();
 								if (!(type.isMarkedNullable() && arg == null) && type.getClassifier() instanceof KClass<?> kClass
 										&& KotlinDetector.isInlineClass(JvmClassMappingKt.getJavaClass(kClass))) {
-									arg = KClasses.getPrimaryConstructor(kClass).call(arg);
+									KFunction<?> valueClassConstructor = KClasses.getPrimaryConstructor(kClass);
+									KCallablesJvm.setAccessible(valueClassConstructor, true);
+									arg = valueClassConstructor.call(arg);
 								}
 								argMap.put(parameter, arg);
 							}
diff --git a/spring-webflux/src/test/kotlin/org/springframework/web/reactive/result/InvocableHandlerMethodKotlinTests.kt b/spring-webflux/src/test/kotlin/org/springframework/web/reactive/result/InvocableHandlerMethodKotlinTests.kt
index 342c20d99f01..bccfa8930db1 100644
--- a/spring-webflux/src/test/kotlin/org/springframework/web/reactive/result/InvocableHandlerMethodKotlinTests.kt
+++ b/spring-webflux/src/test/kotlin/org/springframework/web/reactive/result/InvocableHandlerMethodKotlinTests.kt
@@ -222,6 +222,14 @@ class InvocableHandlerMethodKotlinTests {
 		assertHandlerResultValue(result, "null")
 	}
 
+	@Test
+	fun valueClassWithPrivateConstructor() {
+		this.resolvers.add(stubResolver(1L, Long::class.java))
+		val method = ValueClassController::valueClassWithPrivateConstructor.javaMethod!!
+		val result = invoke(ValueClassController(), method, 1L)
+		assertHandlerResultValue(result, "1")
+	}
+
 	@Test
 	fun propertyAccessor() {
 		this.resolvers.add(stubResolver(null, String::class.java))
@@ -368,6 +376,8 @@ class InvocableHandlerMethodKotlinTests {
 		fun valueClassWithNullable(limit: LongValueClass?) =
 			"${limit?.value}"
 
+		fun valueClassWithPrivateConstructor(limit: ValueClassWithPrivateConstructor) =
+			"${limit.value}"
 	}
 
 	class PropertyAccessorController {
@@ -416,5 +426,12 @@ class InvocableHandlerMethodKotlinTests {
 		}
 	}
 
+	@JvmInline
+	value class ValueClassWithPrivateConstructor private constructor(val value: Long) {
+		companion object {
+			fun from(value: Long) = ValueClassWithPrivateConstructor(value)
+		}
+	}
+
 	class CustomException(message: String) : Throwable(message)
 }
\ No newline at end of file