diff --git a/modules/opencascade/CMakeLists.txt b/modules/opencascade/CMakeLists.txt
index 8fc8795d34..1c15bc43e5 100644
--- a/modules/opencascade/CMakeLists.txt
+++ b/modules/opencascade/CMakeLists.txt
@@ -16,7 +16,6 @@ add_library(sphinxsys_opencascade
     opencascade/surface_shape.h 
     opencascade/vector.cpp 
     opencascade/vector.h
-    opencascade/opencascade.h
 )
 target_include_directories(sphinxsys_opencascade PUBLIC $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/opencascade>)
 target_link_libraries(sphinxsys_opencascade PUBLIC sphinxsys_3d)
diff --git a/modules/opencascade/opencascade/opencascade.h b/modules/opencascade/opencascade/opencascade.h
deleted file mode 100644
index ac27d2e9f8..0000000000
--- a/modules/opencascade/opencascade/opencascade.h
+++ /dev/null
@@ -1,44 +0,0 @@
-/* ------------------------------------------------------------------------- *
- *                                SPHinXsys                                  *
- * ------------------------------------------------------------------------- *
- * SPHinXsys (pronunciation: s'finksis) is an acronym from Smoothed Particle *
- * Hydrodynamics for industrial compleX systems. It provides C++ APIs for    *
- * physical accurate simulation and aims to model coupled industrial dynamic *
- * systems including fluid, solid, multi-body dynamics and beyond with SPH   *
- * (smoothed particle hydrodynamics), a meshless computational method using  *
- * particle discretization.                                                  *
- *                                                                           *
- * SPHinXsys is partially funded by German Research Foundation               *
- * (Deutsche Forschungsgemeinschaft) DFG HU1527/6-1, HU1527/10-1,            *
- *  HU1527/12-1 and HU1527/12-4.                                             *
- *                                                                           *
- * Portions copyright (c) 2017-2023 Technical University of Munich and       *
- * the authors' affiliations.                                                *
- *                                                                           *
- * Licensed under the Apache License, Version 2.0 (the "License"); you may   *
- * not use this file except in compliance with the License. You may obtain a *
- * copy of the License at http://www.apache.org/licenses/LICENSE-2.0.        *
- *                                                                           *
- * ------------------------------------------------------------------------- */
-
-
-#ifndef OPENCASCADE_H
-#define OPENCASCADE_H
-
-#ifdef __linux__
-#pragma GCC system_header // for GCC/CLANG
-#elif _WIN32
-#pragma warning(push, 0) // for MSVC
-#endif
-
-#include "opencascade/STEPCAFControl_Reader.hxx"
-#include"opencascade/TopExp_Explorer.hxx"
-#include"opencascade/TopoDS.hxx"
-#include"opencascade/BRep_Builder.hxx"
-#include"opencascade/GeomAPI_ProjectPointOnSurf.hxx"
-#include "opencascade/gp_Pnt.hxx"
-
-#ifdef _WIN32
-#pragma warning(pop) // for MSVC
-#endif
-#endif // OPENCASCADE_H
\ No newline at end of file
diff --git a/modules/opencascade/opencascade/relax_dynamics_surface.cpp b/modules/opencascade/opencascade/relax_dynamics_surface.cpp
index 83213c404d..daa373e287 100644
--- a/modules/opencascade/opencascade/relax_dynamics_surface.cpp
+++ b/modules/opencascade/opencascade/relax_dynamics_surface.cpp
@@ -1,5 +1,10 @@
+#include "level_set_shape.h"
+#include "surface_shape.h"
 #include "relax_dynamics_surface.h"
 
+#include <opencascade/GeomAPI_ProjectPointOnSurf.hxx>
+#include <opencascade/gp_Pnt.hxx>
+
 //========================================================================================================//
 namespace SPH
 {
diff --git a/modules/opencascade/opencascade/surface_shape.cpp b/modules/opencascade/opencascade/surface_shape.cpp
index 464a34e878..fc889e163d 100644
--- a/modules/opencascade/opencascade/surface_shape.cpp
+++ b/modules/opencascade/opencascade/surface_shape.cpp
@@ -1,5 +1,12 @@
 #include "surface_shape.h"
 
+#include <opencascade/STEPCAFControl_Reader.hxx>
+#include <opencascade/TopExp_Explorer.hxx>
+#include <opencascade/TopoDS.hxx>
+#include <opencascade/BRep_Builder.hxx>
+#include <opencascade/GeomAPI_ProjectPointOnSurf.hxx>
+#include <opencascade/gp_Pnt.hxx>
+
 namespace SPH
 {
 	//=================================================================================================//
diff --git a/modules/opencascade/opencascade/surface_shape.h b/modules/opencascade/opencascade/surface_shape.h
index 021e16c846..b257d69132 100644
--- a/modules/opencascade/opencascade/surface_shape.h
+++ b/modules/opencascade/opencascade/surface_shape.h
@@ -15,7 +15,9 @@
 
 #include "sphinxsys.h" 
 #include "vector.h"
-#include"opencascade.h"
+
+#include <opencascade/Standard_TypeDef.hxx>
+#include <opencascade/Geom_Surface.hxx>
 
 #include <iostream>
 #include <string>
diff --git a/modules/opencascade/opencascade/vector.h b/modules/opencascade/opencascade/vector.h
index f43e8f3ea6..9f83e253fc 100644
--- a/modules/opencascade/opencascade/vector.h
+++ b/modules/opencascade/opencascade/vector.h
@@ -29,7 +29,7 @@
 #define VECTOR_H
 
 #include "base_data_type.h"
-#include"opencascade.h"
+#include <opencascade/gp_Pnt.hxx>
 
 namespace SPH
 {