Abstract: The two westbound typhoons "Mun" and "Weipa" affecting Liangshan Prefecture in 2019 were analyzed by using the real data and NCEP1°×1° Analysis data. The similarities and differences of the duration of heavy rainfall and the falling area in the two processes were analyzed by combining the high altitude impact system and the physical quantity field. The results show that there are many similarities in the influence systems of the two processes; the different locations of subtropical high and Indian monsoon low lead to the different duration and falling areas of the two rainfall processes; the typhoon contributes greatly to the water vapor transport of the two processes,which belongs to the long-distance heavy rainfall caused by typhoon; and the rainstorm points are two. The large value region of ascending motion of the secondary process corresponds well.