Abstract: There are some problems with forged magnesium alloy wheels, such as coarse grains at the spokes, uneven grain size distribution, low recrystallization and easy cracking of the upper rim. In order to refine the microstructure at the spokes, improve the uniformity of the microstructure at the spokes, and improve the performance and yield of the wheel, a truncated cone billet was proposed and the numerical simulation method was used to explore the effect of truncated cone billet on the effective strain, dynamic recrystallization volume fraction, average grain size and damage during the forging of AZ80 magnesium alloy wheel. The results show that compared with the traditional cylindrical billet, the truncated cone billet can obviously change the material flow in the forming process, increase the effective strain of the spokes, significantly increase the recrystallization volume fraction of the spokes, make the grain size distribution uniform and reduce the cracking tendency of the upper rim.