diff --git a/src/SMESH_SWIG/StdMeshersDC.py b/src/SMESH_SWIG/StdMeshersDC.py
index 27b1e7075..3e1abf1d3 100644
--- a/src/SMESH_SWIG/StdMeshersDC.py
+++ b/src/SMESH_SWIG/StdMeshersDC.py
@@ -895,7 +895,7 @@ class StdMeshersDC_Prism3D(Mesh_Algorithm):
         self.mesh.smeshpyD.SetCurrentStudy( None )
         hyp = self.mesh.smeshpyD.CreateHypothesis(hypType, so)
         self.mesh.smeshpyD.SetCurrentStudy( study ) # enables publishing
-        if not distribHyp:
+        if not self.distribHyp:
             self.distribHyp = self.Hypothesis("LayerDistribution", UseExisting=0)
         self.distribHyp.SetLayerDistribution( hyp )
         return hyp