diff --git a/src/slic3r/GUI/Plater.cpp b/src/slic3r/GUI/Plater.cpp
index d43fb3c57..fd966c414 100644
--- a/src/slic3r/GUI/Plater.cpp
+++ b/src/slic3r/GUI/Plater.cpp
@@ -3479,7 +3479,7 @@ std::vector<size_t> Plater::priv::load_files(const std::vector<fs::path>& input_
                 // convert_model_if(model, answer_convert_from_imperial_units == wxID_YES);
             }
 
-             if (model.looks_like_multipart_object()) {
+             if (!is_project_file && model.looks_like_multipart_object()) {
                MessageDialog msg_dlg(q, _L(
                     "This file contains several objects positioned at multiple heights.\n"
                     "Instead of considering them as multiple objects, should \n"