Based on WRF model and FNL reanalysis data, a typical rainstorm process in Early summer in Southeast Part of Guizhou Province from June 17 to 18, 2022 was numerically simulated and terrain sensitivity tests of Leigong Mountain and Moon Mountain were carried out. The results show that the WRF model can well simulate the strong precipitation area and intensity of the process, the convergence and uplift of the shear line in the upper trough and the lower level, and the abundant water vapor brought by the southwest jet stream lead to the occurrence of this rainstorm process. Through terrain sensitivity tests, it was found that the height of Leigong Mountain has decreased, the entire atmospheric wet layer has decreased, the water vapor convergence has weakened, the vertical movement has weakened, and the CAPE value in the south has increased, causing the central precipitation area to shift southward and the precipitation to decrease by more than 35%; The height of Moon Mountain has decreased, combined with favorable terrain in the downstream direction, resulting in enhanced water vapor convergence in the southwestern region, strong convective development, and thick upward motion layers. The CAPE in the southern eastern region has weakened, causing the center of heavy rainfall to shift southward and westward, resulting in an increase in precipitation of over 35%. The decrease in terrain height causes changes in the position and intensity of weather systems at different altitude levels, weakening of 850hPa airflow convergence, and displacement of 700hPa trough positions, resulting in reduced rainfall and changes in precipitation zones.