diff --git a/src/core/MainWindow.cpp b/src/core/MainWindow.cpp
index f405a2e1..7f7165ec 100644
--- a/src/core/MainWindow.cpp
+++ b/src/core/MainWindow.cpp
@@ -700,11 +700,16 @@ RzProjectErr MainWindow::saveProject(bool *canceled)
 
 RzProjectErr MainWindow::saveProjectAs(bool *canceled)
 {
-    QString dir = core->getConfig("prj.file");
-    if (dir.isEmpty()) {
-        dir = QDir(filename).dirName();
+    QString projectFile = core->getConfig("prj.file");
+    if (projectFile.isEmpty()) {
+        // preferred name is of fromat 'binary.exe.rzdb'
+        projectFile = QString("%1.%2").arg(filename).arg("rzdb");
     }
-    QString file = QFileDialog::getSaveFileName(this, tr("Save Project"), dir, PROJECT_FILE_FILTER);
+
+    QFileDialog fileDialog(this);
+    // Append 'rzdb' suffix if it does not exist
+    fileDialog.setDefaultSuffix("rzdb");
+    QString file = fileDialog.getSaveFileName(this, tr("Save Project"), projectFile, PROJECT_FILE_FILTER);
     if (file.isEmpty()) {
         if (canceled) {
             *canceled = true;