diff --git a/src/filewidgets/kfilepreviewgenerator.cpp b/src/filewidgets/kfilepreviewgenerator.cpp
--- a/src/filewidgets/kfilepreviewgenerator.cpp
+++ b/src/filewidgets/kfilepreviewgenerator.cpp
@@ -1017,7 +1017,7 @@
             icon = icon.scaled(maxSize, Qt::KeepAspectRatio, Qt::FastTransformation);
         }
 #else
-        icon = icon.scaled(maxSize, Qt::KeepAspectRatio, Qt::FastTransformation);
+        icon = icon.scaled(maxSize, Qt::KeepAspectRatio, Qt::SmoothTransformation);
 #endif
     }
 }