diff --git a/src/mac/corefoundation/cfstring.cpp b/src/mac/corefoundation/cfstring.cpp
index 078df1e308..2661bb0af8 100644
--- a/src/mac/corefoundation/cfstring.cpp
+++ b/src/mac/corefoundation/cfstring.cpp
@@ -666,6 +666,9 @@ void wxMacCFStringHolder::Assign( const wxString &st , wxFontEncoding encoding )
 
 wxString wxMacCFStringHolder::AsString(wxFontEncoding encoding)
 {
+    if ( m_cfs == NULL )
+        return wxEmptyString ;
+    
     Size cflen = CFStringGetLength( m_cfs )  ;
     size_t noChars ;
     wxChar* buf = NULL ;