Tropical cyclone (TCs) rapid intensification (RI) often results in large forecast errors and it is among the most significant challenges facing operational TCs forecasting centers. In this study, Hato (2017) and Vicente (2012) were selected that have the most significant features happened in the South China Sea in the past 20 years. Based on Fengyun-2 (FY-2) geostationary meteorological satellite high-temporal resolution data, an algorithm for characterizing the cloud in TCs vertical motion signal was developed, which was combinated with vertical wind shear and inner dynamic information. And the authors investigate the interaction between the cloud vertical motion and RI. The results show that the process of RI like the seesaw, with the convection intensity increased and decreased, better organized TCs internal structure was proved TC intensity change with the maximum value of the cloud vertical motion gathered in the core area of the typhoon. The continuous increase of cloud ascending motion within 0~50 km was the most significant contribution to RI, and sudden changes had happened within 1~2 h. The findings corroborate previous RI study results while providing additional insights into internal structure in TC, also it provides references for TC monitoring and future study work.