In order to understand the concentration decay law of sulfuryl fluoride fumigation in warehouses with different airtightness, five warehouses were selected in this experiment. Through the concentration monitoring during the fumigation process, the correlation between the decay half-life of the gas concentration and the air tightness of the warehouses is analyzed and compared. The results show that when the airtightness of the warehouse is 143 s, the maximum concentration half-life is 8.5 d, while with the airtightness of 53 s and 46 s, the maximum concentration half-life are 2.7 d and 4.6 d, respectively. The half-life of gas concentration in warehouses where air-tightness cannot be detected is about 2~3 d. The higher the concentration of sulfuryl fluoride gas, the faster the decay speed, however the concentration decay process does not show a certain connection with the air tightness of the warehouses.