Abstract: In the deepwater drilling, affected by the deepwater section, the overburden pressure is low and the drilling fluid density window is narrow, so higher requirements are raised for the prediction precision of kick tolerance. The kick tolerance is affected by multiple factors, such as kick strength, casing shoe bearing capacity, and intrusive fluid property, and should meet the requirement of safe well killing under the most dangerous working conditions. After the calculation and analysis of deepwater wells in the South China Sea, the effects law of different factors on kick tolerance is figured out, and the notices in kick tolerance analysis of deepwater drilling are raised, so as to provide a reference basis for the deepwater drilling design and site operation. According to the research results, in the deepwater drilling, the different factors effects on the kick tolerance should be fully considered. In particular, in the narrow density window, the calculation precision will affect the wellbore structure and casing lowering depth.