Abstract: Taking the asymmetric and complex cross-section aluminum alloy sunroof guide rail profile with a long arm structure for automobiles as research object, HyperXtrude finite element simulation method was used to study the influence of three key process parameters, including extrusion speed, bar temperature and die temperature, on the metal flow behavior and profile forming quality. The extrusion forming experiment was also verified. The results show that the metal flow velocity distribution in different regions of the profiles under different extrusion processes is similar. The metal flow velocity is highest at the long arm structure, and lower at the short arm structure on the right side of the locking hole. When the extrusion speed is increased from 4 mm/s to 6 mm/s, the profile cross-section velocity at the die exit significantly increases, and its standard deviation（SDV value） increases from 10.56 mm/s to 24.11 mm/s. When the aluminum alloy rod temperature is increased from 440 ℃ to 520 ℃ and the die temperature is increased from 430 ℃ to 510 ℃, the profile cross-section velocity only shows slight changes, but the increase in bar temperature result in an increase in the profile SDV value from 16.49 mm/s to 17.57mm/s, and the increase in die temperature leads to a decrease in the profile SDV value from 23.54 mm/s to 12.63 mm/s. Under the optimal extrusion process（extrusion speed of 4 mm/s, rod temperature of 440 ℃, and die temperature of 510 ℃）, the SDV value of the extruded profile is only 3.59 mm/s, with a temperature of 531.1 ℃-542.6 ℃. After the extrusion testing based on the process, a defect-free aluminum alloy sunroof guide rail profile with good surface quality is obtained.