The effect of typhoon circulation on remote rainstorms is complicated, and extreme precipitation is easy to occur, so it is difficult to forecast accurately the level and falling area. On August 8th, 2014, there were heavy rains from the east of Jiangsu to the north of Zhejiang. Using the numerical forecast situation, the NCEP final operational Global Data and actual observation data, we found collections between the heavy rains and the typhoon “XiaoLong”, 1300 km away on the western Pacific Ocean. The mesoscale vortex mainly caused the rainstorm in the eastern part of Jiangsu Province. The warm and moist air was transmitted to the rainstorm area by the easterly flow of typhoon north side, which was conducive to the formation and maintenance of the rainstorm. Then the rainstorm in the northern part of Zhejiang was caused by the combined effect of the mesoscale vortex and the typhoon circulation. In the process of typhoon moving northward, the distance between the typhoon centre and the vortex shortened, and then the typhoon circulation produced traction on the vortex, which changed the flow field situation. The northwest airflow brought weak cold air to the northern part of Zhejiang and met the warm air in lowlevel in the inshore region, causing convergence uplift and the rainstorm. Then, the convective instability energy broke out, resulting in the mesoscaleγ cyclone, which caused the extreme heavy precipitation.