There were many characters in marine gas reservoir of the northeast Sichuan, such as deeply buried, high-pressure and high temperature, generally sulfur-containing, production changes significantly in flat and vertical. Which lead to the complicated testing technologies, containing the limited tools, complicated downhole accidents, well-control and the risks of the environment. Based on large numbers of laboratory practices and experiences, well testing technology in high-pressure and high-production sulfur-containing gas reservoir were put forward, including three classes of APR perforating and acid fracturing combined well testing string, string mechanical analysis, multi-pressure control, domestic sulfur resistance and compound surface flow process, which could meet all kinds of testing technology requirements. Emergency schemes and strategies ensure the operation safety, including well killing, blowout prevention and leak proof. These technologies were successfully applied in YB1-C1,YB12 , HB11D and other HPHT sulfur-containing wells, which provided technical support for these gas field exploration.