diff --git a/src/slic3r/GUI/Camera.cpp b/src/slic3r/GUI/Camera.cpp
index 7a1023e62..dd6cbefe1 100644
--- a/src/slic3r/GUI/Camera.cpp
+++ b/src/slic3r/GUI/Camera.cpp
@@ -25,6 +25,7 @@ Camera::Camera()
     , phi(45.0f)
 //    , distance(0.0f)
     , requires_zoom_to_bed(false)
+    , inverted_phi(false)
     , m_theta(45.0f)
     , m_target(Vec3d::Zero())
 {
diff --git a/src/slic3r/GUI/Camera.hpp b/src/slic3r/GUI/Camera.hpp
index d19bc870e..b9c5dfc32 100644
--- a/src/slic3r/GUI/Camera.hpp
+++ b/src/slic3r/GUI/Camera.hpp
@@ -22,6 +22,7 @@ struct Camera
     float phi;
 //    float distance;
     bool requires_zoom_to_bed;
+    bool inverted_phi;
 
 private:
     Vec3d m_target;
diff --git a/src/slic3r/GUI/GLCanvas3D.cpp b/src/slic3r/GUI/GLCanvas3D.cpp
index dfddc7f45..d02878a1a 100644
--- a/src/slic3r/GUI/GLCanvas3D.cpp
+++ b/src/slic3r/GUI/GLCanvas3D.cpp
@@ -2729,7 +2729,8 @@ void GLCanvas3D::on_mouse(wxMouseEvent& evt)
             if ((m_hover_volume_id == -1) && m_mouse.is_start_position_3D_defined())
             {
                 const Vec3d& orig = m_mouse.drag.start_position_3D;
-                m_camera.phi += (((float)pos(0) - (float)orig(0)) * TRACKBALLSIZE);
+                float sign = m_camera.inverted_phi ? -1.0f : 1.0f;
+                m_camera.phi += sign * ((float)pos(0) - (float)orig(0)) * TRACKBALLSIZE;
                 m_camera.set_theta(m_camera.get_theta() - ((float)pos(1) - (float)orig(1)) * TRACKBALLSIZE, wxGetApp().preset_bundle->printers.get_edited_preset().printer_technology() != ptSLA);
                 m_dirty = true;
             }
@@ -2781,6 +2782,9 @@ void GLCanvas3D::on_mouse(wxMouseEvent& evt)
                 post_event(SimpleEvent(EVT_GLCANVAS_OBJECT_SELECT));
             }
         }
+        else if (evt.LeftUp() && m_mouse.dragging)
+            // Flips X mouse deltas if bed is upside down
+            m_camera.inverted_phi = (m_camera.get_dir_up()(2) < 0.0);
         else if (evt.RightUp())
         {
             m_mouse.position = pos.cast<double>();