The characteristics of sodium azide gas generating compositions were briefly introduced. Research development of non-azide gas generating compositions was reviewed such as azotic heterocyclic compounds,guanidine derivatives,azoic compounds and complexes of the carbohydrazide and semicarbazide. On the whole,sodium azide based gas generating compositions have the advantages of operating at low temperature and producing almost exclusively N₂ as the output gas,and the most serious downside to them is the toxicity of the sodium azide itself. Non-azide gas generating pyrotechnic compositions are far less toxic than azide systems,but they have bad performance issues such as high operating temperature, ignition difficulties and performance variability.