diff --git a/src/corelib/kernel/qproperty.cpp b/src/corelib/kernel/qproperty.cpp
index f54cd732789..4a8874caf4b 100644
--- a/src/corelib/kernel/qproperty.cpp
+++ b/src/corelib/kernel/qproperty.cpp
@@ -641,11 +641,13 @@ QPropertyObserver::QPropertyObserver(ChangeHandler changeHandler)
     d.setChangeHandler(changeHandler);
 }
 
+#if QT_DEPRECATED_SINCE(6, 6)
 QPropertyObserver::QPropertyObserver(QUntypedPropertyData *data)
 {
     aliasData = data;
     next.setTag(ObserverIsAlias);
 }
+#endif
 
 /*! \internal
 */
diff --git a/src/corelib/kernel/qproperty.h b/src/corelib/kernel/qproperty.h
index 297a3fe9740..5d8b908f31a 100644
--- a/src/corelib/kernel/qproperty.h
+++ b/src/corelib/kernel/qproperty.h
@@ -217,7 +217,9 @@ public:
         ObserverNotifiesBinding, // observer was installed to notify bindings that obsverved property changed
         ObserverNotifiesChangeHandler, // observer is a change handler, which runs on every change
         ObserverIsPlaceholder,  // the observer before this one is currently evaluated in QPropertyObserver::notifyObservers.
+#if QT_DEPRECATED_SINCE(6, 6)
         ObserverIsAlias
+#endif
     };
 protected:
     using ChangeHandler = void (*)(QPropertyObserver*, QUntypedPropertyData *);
@@ -257,7 +259,9 @@ public:
 
 protected:
     QPropertyObserver(ChangeHandler changeHandler);
-    QPropertyObserver(QUntypedPropertyData *aliasedPropertyPtr);
+#if QT_DEPRECATED_SINCE(6, 6)
+    QT_DEPRECATED QPropertyObserver(QUntypedPropertyData *aliasedPropertyPtr);
+#endif
 
     QUntypedPropertyData *aliasedProperty() const
     {
@@ -867,13 +871,16 @@ public:
     }
 };
 
+#if QT_DEPRECATED_SINCE(6, 6)
 template<typename T>
-class QPropertyAlias : public QPropertyObserver
+class QT_DEPRECATED_X("Class was only meant for internal use, use a QProperty and add a binding to the target")
+QPropertyAlias : public QPropertyObserver
 {
     Q_DISABLE_COPY_MOVE(QPropertyAlias)
     const QtPrivate::QBindableInterface *iface = nullptr;
 
 public:
+    QT_WARNING_PUSH QT_WARNING_DISABLE_DEPRECATED
     QPropertyAlias(QProperty<T> *property)
         : QPropertyObserver(property),
           iface(&QtPrivate::QBindableInterfaceForProperty<QProperty<T>>::iface)
@@ -989,7 +996,9 @@ public:
     {
         return aliasedProperty() != nullptr;
     }
+    QT_WARNING_POP
 };
+#endif
 
 template<typename Class, typename T, auto Offset, auto Signal = nullptr>
 class QObjectBindableProperty : public QPropertyData<T>
diff --git a/src/corelib/kernel/qproperty_p.h b/src/corelib/kernel/qproperty_p.h
index 42daca036a7..3ae1bfcc23b 100644
--- a/src/corelib/kernel/qproperty_p.h
+++ b/src/corelib/kernel/qproperty_p.h
@@ -124,13 +124,17 @@ struct QPropertyObserverPointer
     void unlink()
     {
         unlink_common();
+#if QT_DEPRECATED_SINCE(6, 6)
         if (ptr->next.tag() == QPropertyObserver::ObserverIsAlias)
             ptr->aliasData = nullptr;
+#endif
     }
 
     void unlink_fast()
     {
+#if QT_DEPRECATED_SINCE(6, 6)
         Q_ASSERT(ptr->next.tag() != QPropertyObserver::ObserverIsAlias);
+#endif
         unlink_common();
     }
 
@@ -881,8 +885,10 @@ inline void QPropertyObserverPointer::notify(QUntypedPropertyData *propertyDataP
         case QPropertyObserver::ObserverIsPlaceholder:
             // recursion is already properly handled somewhere else
             break;
+#if QT_DEPRECATED_SINCE(6, 6)
         case QPropertyObserver::ObserverIsAlias:
             break;
+#endif
         default: Q_UNREACHABLE();
         }
         observer = next;
diff --git a/tests/auto/corelib/kernel/qproperty/tst_qproperty.cpp b/tests/auto/corelib/kernel/qproperty/tst_qproperty.cpp
index 335cc65b5ab..dbdcaa1a1b2 100644
--- a/tests/auto/corelib/kernel/qproperty/tst_qproperty.cpp
+++ b/tests/auto/corelib/kernel/qproperty/tst_qproperty.cpp
@@ -2240,6 +2240,8 @@ void tst_QProperty::selfBindingShouldNotCrash()
 
 void tst_QProperty::qpropertyAlias()
 {
+#if QT_DEPRECATED_SINCE(6, 6)
+    QT_WARNING_PUSH QT_WARNING_DISABLE_DEPRECATED
     std::unique_ptr<QProperty<int>> i {new QProperty<int>};
     QPropertyAlias<int> alias(i.get());
     QVERIFY(alias.isValid());
@@ -2251,6 +2253,8 @@ void tst_QProperty::qpropertyAlias()
     QCOMPARE(alias.value(), 42);
     i.reset();
     QVERIFY(!alias.isValid());
+    QT_WARNING_POP
+#endif
 }
 
 void tst_QProperty::scheduleNotify()