The invention relates to a low-temperature gas generating agent. The gas generating agent is a composition, wherein the mass percentage of azodicarbonamide in the composition is between 60% and 98%. The gas generating agent provided by the invention has a low gas production temperature, a high inflation speed, a large gas generation amount and a low solid residue content, and can meet requirementsin the field of rapid inflation of capsule bodies or containers and other fields which need rapid generation of low-temperature gas.