Taking the typical hollow aluminum profile with long cantilever as an example,the extrusion process was simulated by using CAE software. The distribution difference of metal flow rate of inlet and outlet sections of the porthole and exit section of the profile in extrusion stabilization stage was analyzed. The design of portholes,welding chamber and the height distribution of die holes was improved,finally the metal flow rate of the exit section of profile was reduced significantly to 14. 50 mm·s-1 from 101...