In this study, to reveal the sub-cloud evaporation and influence factors on it, precipitation events were collected from January 2010 to December 2012, with the corresponding meteorological parameters, that is, amount of precipitation, air temperature and humidity measured in the Dongting Lake Basin, which located in the subtropical monsoon region. It is found that the theoretical slope of the meteoric water lines in different seasons are higher than the observed slope of the meteoric water lines, respectively, and it can be concluded that the ...