Based on the UK reanalysis data,this paper studies and compares the large-scale environmental characteristics of Rapid Intensifying TC (RITC) and Rapid Filling TC (RITC) at 24 h before landing in South China by using the composite analysis method.Results show that the low level inflow and upper level outflow of RITC are significantly stronger than those of RFTC,the intensity difference in high level outflow between RITC and RFTC is more significant than that in low level inflow,and the secondary circulation radial range of RITC is larger than that of RFTC.In terms of the vertical stretching height of outflow,the average outflow of RITC is concentrated on levels above 500 hPa,while the average outflow of RFTC is dispersedly spread down to 850 hPa.The analysis of high level flow field indicates that RITC has stronger high level outflow except in the northwest quadrant,while RFTC only has stronger high level outflow in the northeast quadrant.Correspondingly,there are obvious differences in the range and intensity of upper level divergence between RITC and RFTC,in which the upper level divergence of RITC is stronger than that of RFTC.The abundant southwest monsoon water vapor transportation can promote TC intensifying rapidly before landing in South China,and the convective activity of RITC is obviously stronger than that of RFTC.The tropospheric vertical wind shear of RITC is weaker than that of RFTC,which is beneficial to the intensifying of RITC.