diff --git a/src/slic3r/GUI/Gizmos/GLGizmoMmuSegmentation.cpp b/src/slic3r/GUI/Gizmos/GLGizmoMmuSegmentation.cpp
index c1265887d..4d555f6ab 100644
--- a/src/slic3r/GUI/Gizmos/GLGizmoMmuSegmentation.cpp
+++ b/src/slic3r/GUI/Gizmos/GLGizmoMmuSegmentation.cpp
@@ -250,7 +250,7 @@ void GLGizmoMmuSegmentation::render_triangles(const Selection &selection) const
 bool GLGizmoMmuSegmentation::on_number_key_down(int number)
 {
     int extruder_idx = number - 1;
-    if (extruder_idx < m_extruders_colors.size())
+    if (extruder_idx < m_extruders_colors.size() && extruder_idx >= 0)
         m_selected_extruder_idx = extruder_idx;
 
     return true;
@@ -523,7 +523,7 @@ void GLGizmoMmuSegmentation::on_render_input_window(float x, float y, float bott
         color_button_high = ImGui::GetCursorPos().y - color_button - 2.0;
         if (color_picked) { m_selected_extruder_idx = extruder_idx; }
 
-        if (extruder_idx < 9 && ImGui::IsItemHovered()) m_imgui->tooltip(_L("Shortcut Key ") + std::to_string(extruder_idx + 1), max_tooltip_width);
+        if (extruder_idx < 16 && ImGui::IsItemHovered()) m_imgui->tooltip(_L("Shortcut Key ") + std::to_string(extruder_idx + 1), max_tooltip_width);
 
         // draw filament id
         float gray = 0.299 * extruder_color[0] + 0.587 * extruder_color[1] + 0.114 * extruder_color[2];
diff --git a/src/slic3r/GUI/Gizmos/GLGizmosManager.cpp b/src/slic3r/GUI/Gizmos/GLGizmosManager.cpp
index 9c4e59293..693434002 100644
--- a/src/slic3r/GUI/Gizmos/GLGizmosManager.cpp
+++ b/src/slic3r/GUI/Gizmos/GLGizmosManager.cpp
@@ -50,6 +50,7 @@ GLGizmosManager::GLGizmosManager(GLCanvas3D& parent)
     //BBS: GUI refactor: add object manipulation in gizmo
     , m_object_manipulation(parent)
 {
+    m_timer_set_color.Bind(wxEVT_TIMER, &GLGizmosManager::on_set_color_timer, this);
 }
 
 std::vector<size_t> GLGizmosManager::get_selectable_idxs() const
@@ -1250,8 +1251,18 @@ bool GLGizmosManager::on_key(wxKeyEvent& evt)
         else if (m_current == MmuSegmentation) {
             GLGizmoMmuSegmentation* mmu_seg = dynamic_cast<GLGizmoMmuSegmentation*>(get_current());
             if (mmu_seg != nullptr) {
-                if (keyCode > '0' && keyCode <= '9') {
-                    processed = mmu_seg->on_number_key_down(keyCode - '0');
+                if (keyCode >= '0' && keyCode <= '9') {
+                    if (keyCode == '1' && !m_timer_set_color.IsRunning()) {
+                        m_timer_set_color.StartOnce(500);
+                        processed = true;
+                    }
+                    else if (keyCode < '7' && m_timer_set_color.IsRunning()) {
+                        processed = mmu_seg->on_number_key_down(keyCode - '0'+10);
+                        m_timer_set_color.Stop();
+                    }
+                    else {
+                        processed = mmu_seg->on_number_key_down(keyCode - '0');
+                    }
                 }
                 else if (keyCode == 'F' || keyCode == 'T' || keyCode == 'S' || keyCode == 'C' || keyCode == 'H' || keyCode == 'G') {
                     processed = mmu_seg->on_key_down_select_tool_type(keyCode);
@@ -1290,6 +1301,15 @@ bool GLGizmosManager::on_key(wxKeyEvent& evt)
     return processed;
 }
 
+void GLGizmosManager::on_set_color_timer(wxTimerEvent& evt)
+{
+    if (m_current == MmuSegmentation) {
+        GLGizmoMmuSegmentation* mmu_seg = dynamic_cast<GLGizmoMmuSegmentation*>(get_current());
+        mmu_seg->on_number_key_down(1);
+        m_parent.set_as_dirty();
+    }
+}
+
 void GLGizmosManager::update_after_undo_redo(const UndoRedo::Snapshot& snapshot)
 {
     update_data();
diff --git a/src/slic3r/GUI/Gizmos/GLGizmosManager.hpp b/src/slic3r/GUI/Gizmos/GLGizmosManager.hpp
index 61f57142a..1ca807c6f 100644
--- a/src/slic3r/GUI/Gizmos/GLGizmosManager.hpp
+++ b/src/slic3r/GUI/Gizmos/GLGizmosManager.hpp
@@ -143,6 +143,10 @@ private:
     bool m_serializing;
     std::unique_ptr<CommonGizmosDataPool> m_common_gizmos_data;
 
+    //When there are more than 9 colors, shortcut key coloring
+    wxTimer m_timer_set_color;
+    void on_set_color_timer(wxTimerEvent& evt);
+
     // key MENU_ICON_NAME, value = ImtextureID
     std::map<int, void*> icon_list;