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• Activity and stability of Ga/ZSM-5 were improved by H 2 -O 2 treatment. • Effective balance of dehydrogenation and cracking of Ga/ZSM-5 was achieved. • Activation energy was decreased largely for Ga/ZSM-5 after H 2 -O 2 treatment. • The mechanism of butane-O 2 treatment on Ga/ZSM-5 was proposed. Ga species with high dehydrogenation capability were prepared by H 2 -O 2 atmosphere treatment, and efficient balance of bifunctionality (dehydrogenation/cracking) was realized between Ga species and ZSM-5 over Ga/ZSM-5 based catalysts. Compared with parent Ga/ZSM-5, the conversion rate of n -butane was increased from 0.53 to 2.59 mmol·g−1·min−1 on Ga/ZSM-5 with H 2 -O 2 treatment. Kinetic analysis revealed that the apparent activation energy of n -butane catalytic cracking decreased largely from 141 to 47 kJ·mol−1, which is attributed to the formation of new interaction between Ga species and ZSM-5 upon such an atmosphere treatment. It was also found Butane-O 2 treatment acted as a similar role with H 2 -O 2 treatment in enhancing the catalytic performance. On this basis, different Ga species were correlated with activity and kinetic data, and the effect of practical reaction atmosphere on Ga species was also investigated. [ABSTRACT FROM AUTHOR]