The synchronous ring is an essential part being a dissymmetrical component with several spline and ringlike thin wall widely used in the heavy vehicles and buses.As the precision forming technology has not been solved,the production cost is high and the efficiency is very low.There are mainly following questions.Firstly some profiles of the synchronous ring can not be filled properly.Secondly the material utilization ratio is very low,generally not up to 40%.Lastly the die life is very short.In this paper the forming process of the synchronous ring is simulated by finite-element method.The rules of the material flowing in the cavity in different forming stages are analyzed.The effects of the die structure and the blank size on the quality of the product are also analyzed.The result of failure analysis shows that the main reason is the temperature on the surface increasing in hot forging causing die softening.In order to prolong the die life and improve the quality of the workpiece,forming technology is improved adopting synthetic forming process.Experiment verification shows that the die life has been greatly improved.The actual production is around 400-600 pieces when using one forging method,the lifetime of preforming cavity has reached 1200-1500 pieces when using the synthetic forming technology,and the lifetime of finish forming cavity has reached about 3000-3500 pieces.It plays quite remarkable economic benefit and technology value.