diff --git a/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosticCompilerTestFE10TestdataTestGenerated.java b/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosticCompilerTestFE10TestdataTestGenerated.java
index 0c43d64966a..515b80a2c0f 100644
--- a/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosticCompilerTestFE10TestdataTestGenerated.java
+++ b/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/DiagnosticCompilerTestFE10TestdataTestGenerated.java
@@ -22074,6 +22074,12 @@ public class DiagnosticCompilerTestFE10TestdataTestGenerated extends AbstractDia
                 runTest("compiler/testData/diagnostics/tests/j+k/KJKInheritanceGeneric.kt");
             }
 
+            @Test
+            @TestMetadata("kjkPropertyAndExtensionProperty.kt")
+            public void testKjkPropertyAndExtensionProperty() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/j+k/kjkPropertyAndExtensionProperty.kt");
+            }
+
             @Test
             @TestMetadata("kt1402.kt")
             public void testKt1402() throws Exception {
diff --git a/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated.java b/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated.java
index be04bce334c..0a2c4a4d512 100644
--- a/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated.java
+++ b/analysis/low-level-api-fir/tests/org/jetbrains/kotlin/analysis/low/level/api/fir/diagnostic/compiler/based/LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated.java
@@ -22074,6 +22074,12 @@ public class LLFirPreresolvedReversedDiagnosticCompilerFE10TestDataTestGenerated
                 runTest("compiler/testData/diagnostics/tests/j+k/KJKInheritanceGeneric.kt");
             }
 
+            @Test
+            @TestMetadata("kjkPropertyAndExtensionProperty.kt")
+            public void testKjkPropertyAndExtensionProperty() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/j+k/kjkPropertyAndExtensionProperty.kt");
+            }
+
             @Test
             @TestMetadata("kt1402.kt")
             public void testKt1402() throws Exception {
diff --git a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirLightTreeOldFrontendDiagnosticsTestGenerated.java b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirLightTreeOldFrontendDiagnosticsTestGenerated.java
index f1f9223ae73..f0efa1d0af4 100644
--- a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirLightTreeOldFrontendDiagnosticsTestGenerated.java
+++ b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirLightTreeOldFrontendDiagnosticsTestGenerated.java
@@ -22068,6 +22068,12 @@ public class FirLightTreeOldFrontendDiagnosticsTestGenerated extends AbstractFir
                 runTest("compiler/testData/diagnostics/tests/j+k/KJKInheritanceGeneric.kt");
             }
 
+            @Test
+            @TestMetadata("kjkPropertyAndExtensionProperty.kt")
+            public void testKjkPropertyAndExtensionProperty() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/j+k/kjkPropertyAndExtensionProperty.kt");
+            }
+
             @Test
             @TestMetadata("kt1402.kt")
             public void testKt1402() throws Exception {
diff --git a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirPsiOldFrontendDiagnosticsTestGenerated.java b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirPsiOldFrontendDiagnosticsTestGenerated.java
index 9b5debc9053..8b2bfd15de3 100644
--- a/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirPsiOldFrontendDiagnosticsTestGenerated.java
+++ b/compiler/fir/analysis-tests/tests-gen/org/jetbrains/kotlin/test/runners/FirPsiOldFrontendDiagnosticsTestGenerated.java
@@ -22074,6 +22074,12 @@ public class FirPsiOldFrontendDiagnosticsTestGenerated extends AbstractFirPsiDia
                 runTest("compiler/testData/diagnostics/tests/j+k/KJKInheritanceGeneric.kt");
             }
 
+            @Test
+            @TestMetadata("kjkPropertyAndExtensionProperty.kt")
+            public void testKjkPropertyAndExtensionProperty() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/j+k/kjkPropertyAndExtensionProperty.kt");
+            }
+
             @Test
             @TestMetadata("kt1402.kt")
             public void testKt1402() throws Exception {
diff --git a/compiler/fir/java/src/org/jetbrains/kotlin/fir/java/scopes/JavaClassUseSiteMemberScope.kt b/compiler/fir/java/src/org/jetbrains/kotlin/fir/java/scopes/JavaClassUseSiteMemberScope.kt
index 05d8ca3fc76..21d28dc4331 100644
--- a/compiler/fir/java/src/org/jetbrains/kotlin/fir/java/scopes/JavaClassUseSiteMemberScope.kt
+++ b/compiler/fir/java/src/org/jetbrains/kotlin/fir/java/scopes/JavaClassUseSiteMemberScope.kt
@@ -46,7 +46,6 @@ import org.jetbrains.kotlin.name.CallableId
 import org.jetbrains.kotlin.name.Name
 import org.jetbrains.kotlin.name.StandardClassIds
 import org.jetbrains.kotlin.types.AbstractTypeChecker
-import org.jetbrains.kotlin.utils.addIfNotNull
 import org.jetbrains.kotlin.utils.addToStdlib.runIf
 
 /**
@@ -141,8 +140,8 @@ class JavaClassUseSiteMemberScope(
         }
 
         /*
-         * From supertype we can get at most two results:
-         * 1. Set of properties with same name
+         * From supertype we can get:
+         * 1. Set of properties with same name (including regular and extension properties)
          * 2. Field from some java superclass (only one, if class have more than one superclass then we can choose
          *   just one field because this is incorrect code anyway)
          */
@@ -153,23 +152,24 @@ class JavaClassUseSiteMemberScope(
         }
 
         assert(fieldsFromSupertype.size in 0..1)
-        assert(propertiesFromSupertypes.size in 0..1)
 
         fieldsFromSupertype.firstOrNull()?.chosenSymbol?.let { fieldSymbol ->
             require(fieldSymbol is FirFieldSymbol)
             if (fieldSymbol.name !in fieldNames) {
-                result.addIfNotNull(fieldSymbol)
+                result.add(fieldSymbol)
             }
         }
 
         @Suppress("UNCHECKED_CAST")
-        val overriddenProperty = propertiesFromSupertypes.firstOrNull() as ResultOfIntersection<FirPropertySymbol>? ?: return result
-        val overrideInClass = syntheticPropertyCache.getValue(name, this to overriddenProperty)
+        for (overriddenProperty in propertiesFromSupertypes as List<ResultOfIntersection<FirPropertySymbol>>) {
+            val overrideInClass = syntheticPropertyCache.getValue(name, this to overriddenProperty)
+
+            val chosenSymbol = overrideInClass ?: overriddenProperty.chosenSymbol
+            directOverriddenProperties[chosenSymbol] = listOf(overriddenProperty)
+            overriddenProperty.overriddenMembers.forEach { overrideByBase[it.member] = overrideInClass }
+            result += chosenSymbol
+        }
 
-        val chosenSymbol = overrideInClass ?: overriddenProperty.chosenSymbol
-        directOverriddenProperties[chosenSymbol] = listOf(overriddenProperty)
-        overriddenProperty.overriddenMembers.forEach { overrideByBase[it.member] = overrideInClass }
-        result += chosenSymbol
         return result
     }
 
diff --git a/compiler/testData/diagnostics/tests/j+k/kjkPropertyAndExtensionProperty.fir.kt b/compiler/testData/diagnostics/tests/j+k/kjkPropertyAndExtensionProperty.fir.kt
new file mode 100644
index 00000000000..fdd4e5ae8c3
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/j+k/kjkPropertyAndExtensionProperty.fir.kt
@@ -0,0 +1,70 @@
+// ISSUE: KT-65373, KT-65464
+
+// FILE: J.java
+public class J extends D {}
+
+// FILE: JOverridesRegular.java
+public class JOverridesRegular extends D {
+    @Override
+    public int getA() {
+        return 1;
+    }
+}
+
+// FILE: JOverridesExtension.java
+public class JOverridesExtension extends D {
+    @Override
+    public int getA(String $this) {
+        return 1;
+    }
+}
+
+// FILE: JOVerridesBoth.java
+public class JOVerridesBoth extends D {
+    @Override
+    public int getA() {
+        return 1;
+    }
+
+    @Override
+    public int getA(String $this) {
+        return 1;
+    }
+}
+
+// FILE: 1.kt
+open class D {
+    open val a: Int
+        get() = 2
+
+    open val String.a: Int
+        get() = 1
+}
+
+class F : J() {
+    fun test() {
+        a
+        "".a
+    }
+}
+
+class F2 : JOverridesRegular() {
+    fun test() {
+        a
+        "".<!UNRESOLVED_REFERENCE!>a<!>
+    }
+}
+
+class F3 : JOverridesExtension() {
+    fun test() {
+        a
+        "".a
+    }
+}
+
+class F4 : JOVerridesBoth() {
+    fun test() {
+        a
+        "".<!UNRESOLVED_REFERENCE!>a<!>
+    }
+}
diff --git a/compiler/testData/diagnostics/tests/j+k/kjkPropertyAndExtensionProperty.kt b/compiler/testData/diagnostics/tests/j+k/kjkPropertyAndExtensionProperty.kt
new file mode 100644
index 00000000000..947a47e52a3
--- /dev/null
+++ b/compiler/testData/diagnostics/tests/j+k/kjkPropertyAndExtensionProperty.kt
@@ -0,0 +1,70 @@
+// ISSUE: KT-65373, KT-65464
+
+// FILE: J.java
+public class J extends D {}
+
+// FILE: JOverridesRegular.java
+public class JOverridesRegular extends D {
+    @Override
+    public int getA() {
+        return 1;
+    }
+}
+
+// FILE: JOverridesExtension.java
+public class JOverridesExtension extends D {
+    @Override
+    public int getA(String $this) {
+        return 1;
+    }
+}
+
+// FILE: JOVerridesBoth.java
+public class JOVerridesBoth extends D {
+    @Override
+    public int getA() {
+        return 1;
+    }
+
+    @Override
+    public int getA(String $this) {
+        return 1;
+    }
+}
+
+// FILE: 1.kt
+open class D {
+    open val a: Int
+        get() = 2
+
+    open val String.a: Int
+        get() = 1
+}
+
+class F : J() {
+    fun test() {
+        a
+        "".a
+    }
+}
+
+class F2 : JOverridesRegular() {
+    fun test() {
+        a
+        "".a
+    }
+}
+
+class <!CONFLICTING_INHERITED_JVM_DECLARATIONS!>F3<!> : JOverridesExtension() {
+    fun test() {
+        a
+        "".a
+    }
+}
+
+class <!CONFLICTING_INHERITED_JVM_DECLARATIONS!>F4<!> : JOVerridesBoth() {
+    fun test() {
+        a
+        "".a
+    }
+}
diff --git a/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/DiagnosticTestGenerated.java b/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/DiagnosticTestGenerated.java
index 708d14911fa..759dea4f20c 100644
--- a/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/DiagnosticTestGenerated.java
+++ b/compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/DiagnosticTestGenerated.java
@@ -22074,6 +22074,12 @@ public class DiagnosticTestGenerated extends AbstractDiagnosticTest {
                 runTest("compiler/testData/diagnostics/tests/j+k/KJKInheritanceGeneric.kt");
             }
 
+            @Test
+            @TestMetadata("kjkPropertyAndExtensionProperty.kt")
+            public void testKjkPropertyAndExtensionProperty() throws Exception {
+                runTest("compiler/testData/diagnostics/tests/j+k/kjkPropertyAndExtensionProperty.kt");
+            }
+
             @Test
             @TestMetadata("kt1402.kt")
             public void testKt1402() throws Exception {