diff --git a/src/OpenGl/OpenGl_ShaderManager.cxx b/src/OpenGl/OpenGl_ShaderManager.cxx
index ababd4359d..e5c143a53b 100644
--- a/src/OpenGl/OpenGl_ShaderManager.cxx
+++ b/src/OpenGl/OpenGl_ShaderManager.cxx
@@ -2731,9 +2731,10 @@ Standard_Boolean OpenGl_ShaderManager::prepareStdProgramPhong (Handle(OpenGl_Sha
         EOL"    aDeltaUVMatrix = mat2 (aDeltaUVMatrix[1][1], -aDeltaUVMatrix[0][1], -aDeltaUVMatrix[1][0], aDeltaUVMatrix[0][0]);"
         EOL"    mat2x3 aDeltaVectorMatrix = mat2x3 (dFdx (PositionWorld.xyz), dFdy (PositionWorld.xyz));"
         EOL"    aDeltaVectorMatrix = aDeltaVectorMatrix * aDeltaUVMatrix;"
-        EOL"    aDeltaVectorMatrix[0] = aDeltaVectorMatrix[0] - dot(Normal, aDeltaVectorMatrix[0]) * Normal;"
-        EOL"    aDeltaVectorMatrix[1] = aDeltaVectorMatrix[1] - dot(Normal, aDeltaVectorMatrix[1]) * Normal;"
-        EOL"    Normal = mat3 (-normalize(aDeltaVectorMatrix[0]), -normalize(aDeltaVectorMatrix[1]), Normal) * aMapNormalValue.xyz;"
+        EOL"    aDeltaVectorMatrix[0] = normalize(aDeltaVectorMatrix[0] - dot(Normal, aDeltaVectorMatrix[0]) * Normal);"
+        EOL"    aDeltaVectorMatrix[1] = normalize(aDeltaVectorMatrix[1] - dot(Normal, aDeltaVectorMatrix[1]) * Normal);"
+        EOL"    float aDirection = gl_FrontFacing ? 1.0 : -1.0;"
+        EOL"    Normal = mat3 (aDirection * aDeltaVectorMatrix[0], aDirection * aDeltaVectorMatrix[1], Normal) * aMapNormalValue.xyz;"
         EOL"  }"
         EOL"#endif";
     }
diff --git a/tests/v3d/glsl/pbr_tangent_normal b/tests/v3d/glsl/pbr_tangent_normal
new file mode 100644
index 0000000000..ade81c7d42
--- /dev/null
+++ b/tests/v3d/glsl/pbr_tangent_normal
@@ -0,0 +1,28 @@
+puts "========"
+puts "0031302: Visualization, TKOpenGl - wrong tangent space calculation for normal maps"
+puts "Test for tangent space orientation."
+puts "========"
+
+pload XDE OCAF MODELING VISUALIZATION
+
+vclear
+vclose ALL
+
+vinit v -w 1024 -h 1024
+vcamera -persp
+vbackground -cubemap [locate_data_file Circus_CubeMap_V.png]
+vrenderparams -shadingModel PBR
+
+vlight -clear
+vlight -add ambient
+
+catch { Close D }
+ReadGltf D [locate_data_file bug31302_NormalTangentTest.gltf]
+XDisplay -dispmode 1 D
+
+vfront
+vfit
+vdump $imagedir/${casename}_front.png
+
+vback
+vdump $imagedir/${casename}_back.png