diff --git a/python/plugins/mapserver_export/ms_export.py b/python/plugins/mapserver_export/ms_export.py
index d48b6c71816..e68cc068a57 100644
--- a/python/plugins/mapserver_export/ms_export.py
+++ b/python/plugins/mapserver_export/ms_export.py
@@ -308,7 +308,8 @@ class Qgis2Map:
         self.outFile.write("    CONNECTIONTYPE postgis\n")
         self.outFile.write("    CONNECTION '" + pgConnString + "'\n")
         self.outFile.write("    DATA '" + sqlData + "'\n")
-        self.outFile.write("    FILTER '" + sqlFilter + "'\n")
+        if sqlFilter:
+          self.outFile.write("    FILTER '" + sqlFilter + "'\n")
 
       elif providerString == 'wms' and lyr.getAttribute("type").encode('utf-8').upper() == 'RASTER':
         # it's a WMS layer