Some characteristics of nanocrystalline La1-xSrxFeO3──based materials with differ-ent x values, especially. It's gas-sensing properties have been studied. Results showLa0. 6Sr0. 4FeO3 and La0. 4Sr0. 6FeO3──based material with very high sensitivity and good selectivi-ty and response recovery propertiesto C2H5OH.