diff --git a/src/App/Document.cpp b/src/App/Document.cpp
index 5d8a170204..988803e236 100644
--- a/src/App/Document.cpp
+++ b/src/App/Document.cpp
@@ -83,6 +83,7 @@ recompute path. Also, it enables more complicated dependencies beyond trees.
 #include <QCoreApplication>
 
 #include <App/DocumentPy.h>
+#include <Base/Interpreter.h>
 #include <Base/Console.h>
 #include <Base/Exception.h>
 #include <Base/FileInfo.h>
@@ -793,6 +794,7 @@ Document::Document(const char* documentName)
     // Remark: We force the document Python object to own the DocumentPy instance, thus we don't
     // have to care about ref counting any more.
     d = new DocumentP;
+    Base::PyGILStateLocker lock;
     d->DocumentPythonObject = Py::Object(new DocumentPy(this), true);
 
 #ifdef FC_LOGUPDATECHAIN
diff --git a/src/Gui/Document.cpp b/src/Gui/Document.cpp
index e6f01ef63a..b6bdeb950f 100644
--- a/src/Gui/Document.cpp
+++ b/src/Gui/Document.cpp
@@ -220,6 +220,7 @@ Document::Document(App::Document* pcDocument,Application * app)
     // pointer to the python class
     // NOTE: As this Python object doesn't get returned to the interpreter we
     // mustn't increment it (Werner Jan-12-2006)
+    Base::PyGILStateLocker lock;
     _pcDocPy = new Gui::DocumentPy(this);
 
     ParameterGrp::handle hGrp = App::GetApplication().GetParameterGroupByPath("User parameter:BaseApp/Preferences/Document");