Objective To consummate genetic biochemical marker of inbred mice，we study Catalase-2 of biochemical markers of inbred mice． Methods Filial generation 1 CCBF1 were abtained by intercrossing of CBA /Ca and BALB / c; and filial generation 1 B6CBF1 were also abtained by intercrossing of CBA /Ca and C57BL /6． Filial generation 2 were obtained by intercrossing between filial generation 1 and by backcrossing between filial generation 1 and their parents．Then filial generation 2 were monitored by biochemical markers． Result Ce-2b is detected among filial generation 2 mice，while not among filial generation 1 mice． Conclusion Ce-2a is fully dominant．