diff --git a/dlls/d3drm/d3drm.spec b/dlls/d3drm/d3drm.spec
index 00412654134..4347160ecb5 100644
--- a/dlls/d3drm/d3drm.spec
+++ b/dlls/d3drm/d3drm.spec
@@ -9,7 +9,7 @@
 @ stub D3DRMQuaternionMultiply
 @ stub D3DRMQuaternionSlerp
 @ stdcall D3DRMVectorAdd(ptr ptr ptr)
-@ stub D3DRMVectorCrossProduct
+@ stdcall D3DRMVectorCrossProduct(ptr ptr ptr)
 @ stub D3DRMVectorDotProduct
 @ stub D3DRMVectorModulus
 @ stub D3DRMVectorNormalize
diff --git a/dlls/d3drm/math.c b/dlls/d3drm/math.c
index fd5b490158c..39b96d0247f 100644
--- a/dlls/d3drm/math.c
+++ b/dlls/d3drm/math.c
@@ -49,3 +49,12 @@ LPD3DVECTOR WINAPI D3DRMVectorSubtract(LPD3DVECTOR d, LPD3DVECTOR s1, LPD3DVECTO
     d->z=s1->z - s2->z;
     return d;
 }
+
+/* Cross Product of Two Vectors */
+LPD3DVECTOR WINAPI D3DRMVectorCrossProduct(LPD3DVECTOR d, LPD3DVECTOR s1, LPD3DVECTOR s2)
+{
+    d->x=s1->y * s2->z - s1->z * s2->y;
+    d->y=s1->z * s2->x - s1->x * s2->z;
+    d->z=s1->x * s2->y - s1->y * s2->x;
+    return d;
+}
diff --git a/dlls/d3drm/tests/vector.c b/dlls/d3drm/tests/vector.c
index 68deea4cc09..52c81e892b5 100644
--- a/dlls/d3drm/tests/vector.c
+++ b/dlls/d3drm/tests/vector.c
@@ -46,6 +46,11 @@ void VectorTest(void)
     D3DRMVectorSubtract(&r,&u,&v);
     e.x=-2.0;e.y=-2.0;e.z=1.0;
     expect_vec(e,r);
+
+/*_______________________VectorCrossProduct_______________________*/
+    D3DRMVectorCrossProduct(&r,&u,&v);
+    e.x=-4.0;e.y=4.0;e.z=0.0;
+    expect_vec(e,r);
 }
 
 START_TEST(vector)