Abstract: Using the routine upper-air and surface weather station observations and NCEP/NCAR 6-hourly reanalysis data with resolution1°×1°, a comparative analysis is made on the two rainstorm processes happened from July 23 to 24, 2010 and from September 17 to 18, 2011 respectively affected by distant typhoons. The results indicate that the typhoons affect the two rainstorm processes in very different ways. In the former process, water vapor and energy in and near low level jet (LLJ) are conveyed by typhoon to the rainstorm region and this process is characterized by high precipitation efficiency and great intensity. In the latter one a similar easterly disturbance triggered by typhoon as disturbance source propagates westerly and meets with westerlies synoptic systems over the eastern Sichuan and the eastern Tibetan Plateau enlarging pressure gradient of the rainstorm region, inducing LLJ and strengthening moisture convergence of the rainstorm region, so that the maintenance of westerlies synoptic systems are lengthened in the rainstorm region making precipitation duration longer.