diff --git a/src/gui/math3d/qquaternion.cpp b/src/gui/math3d/qquaternion.cpp
index 0d65b1f839..5e23996c15 100644
--- a/src/gui/math3d/qquaternion.cpp
+++ b/src/gui/math3d/qquaternion.cpp
@@ -314,13 +314,6 @@ void QQuaternion::normalize()
     (-x, -y, -z, scalar).
 */
 
-/*!
-    \fn QQuaternion QQuaternion::conjugate() const
-    \obsolete
-
-    Use conjugated() instead.
-*/
-
 /*!
     Rotates \a vector with this quaternion to produce a new vector
     in 3D space.  The following code:
diff --git a/src/gui/math3d/qquaternion.h b/src/gui/math3d/qquaternion.h
index 12d62e8f50..cfe495530e 100644
--- a/src/gui/math3d/qquaternion.h
+++ b/src/gui/math3d/qquaternion.h
@@ -96,9 +96,6 @@ public:
     inline QQuaternion inverted() const;
 
     Q_REQUIRED_RESULT QQuaternion conjugated() const;
-#if QT_DEPRECATED_SINCE(5, 5)
-    Q_REQUIRED_RESULT QT_DEPRECATED QQuaternion conjugate() const;
-#endif
 
     QVector3D rotatedVector(const QVector3D& vector) const;
 
@@ -220,13 +217,6 @@ inline QQuaternion QQuaternion::conjugated() const
     return QQuaternion(wp, -xp, -yp, -zp);
 }
 
-#if QT_DEPRECATED_SINCE(5, 5)
-inline QQuaternion QQuaternion::conjugate() const
-{
-    return conjugated();
-}
-#endif
-
 inline QQuaternion &QQuaternion::operator+=(const QQuaternion &quaternion)
 {
     wp += quaternion.wp;
diff --git a/tests/auto/gui/math3d/qquaternion/tst_qquaternion.cpp b/tests/auto/gui/math3d/qquaternion/tst_qquaternion.cpp
index 632460f5ff..3db53be2ab 100644
--- a/tests/auto/gui/math3d/qquaternion/tst_qquaternion.cpp
+++ b/tests/auto/gui/math3d/qquaternion/tst_qquaternion.cpp
@@ -121,8 +121,8 @@ private slots:
     void negate_data();
     void negate();
 
-    void conjugate_data();
-    void conjugate();
+    void conjugated_data();
+    void conjugated();
 
     void fromAxisAndAngle_data();
     void fromAxisAndAngle();
@@ -763,12 +763,12 @@ void tst_QQuaternion::negate()
 }
 
 // Test quaternion conjugate calculations.
-void tst_QQuaternion::conjugate_data()
+void tst_QQuaternion::conjugated_data()
 {
     // Use the same test data as the add test.
     add_data();
 }
-void tst_QQuaternion::conjugate()
+void tst_QQuaternion::conjugated()
 {
     QFETCH(float, x1);
     QFETCH(float, y1);
@@ -778,9 +778,6 @@ void tst_QQuaternion::conjugate()
     QQuaternion v1(w1, x1, y1, z1);
     QQuaternion v2(w1, -x1, -y1, -z1);
 
-#if QT_DEPRECATED_SINCE(5, 5)
-    QCOMPARE(v1.conjugate(), v2);
-#endif
     QCOMPARE(v1.conjugated(), v2);
 }