The theraml behaviour of fifteen nitrosubstituted azetidines,3,3-dinitroazetidinium dinitramide (1),3,3-dinitroazetidinium nitrate (2),3,3-dinitroazetidinium nitroform salt (3),3,3-dinitroazetidinium-3,5- dinitrobenzoate (4),3,3-dinitroazetidinium picrate (5),3,3-dinitroazetidinium-3-nitro-1,2,4-triazol-5-onate (6),1,3-bis(3′，3′-dinitroazetidine group)-2,2-dinitropropane (7),1-（2′，2′，2′-trinitroethyl）-3，3-dinitroazetidine (8), 3，3-dinitroazetidinium perchlorate (9),1-（ 3′，3′-dinitroazetidineyl）-2，2-dinitropropane（10）, 3，3-dinitroazetidinium-2，4，6-trinitrobenzoate （11）,bis（3′，3′-dinitroazetidine）ketone （12）,1-（ 2′，4′-dinitrophenyl）-3，3-dinitroazetidine （13）, 1-（2′，4′，6′-trinitrophenyl）-3，3-dinitroazetidine （14）, bis（3′，3′-dinitroazetidineyl）oxalone (15) in static air has been studied by means of differential scanning calorimetry. On the basis of the results obtained,the relative thermal stability order and two relationship between the kinetic parameters,and the exathermic decomposition temperature and thermal explosion critical temperature for above-mentioned nitrosubstituted azetidines are proposed.