diff --git a/python/plugins/processing/core/GeoAlgorithm.py b/python/plugins/processing/core/GeoAlgorithm.py
index c0c7b3cf09f..c90fb052389 100644
--- a/python/plugins/processing/core/GeoAlgorithm.py
+++ b/python/plugins/processing/core/GeoAlgorithm.py
@@ -435,7 +435,7 @@ class GeoAlgorithm:
                             if layer.name() == inputlayer:
                                 inputlayers[i] = layer.source()
                                 break
-                    param.setValue(",".join(inputlayers))
+                    param.setValue(";".join(inputlayers))
 
     def checkInputCRS(self):
         """It checks that all input layers use the same CRS. If so,