The specific activities of succinate dehydrogenase, lactate dehydrogenase and cytochrome oxydase were identified in three kinds of liver cells of mice: normal liver, liver of the cancer bearing mice and the cancer self. The results show that: 1) The specific activity of succinate dehydrogenase on cancer cells significantly lower than that of the normal (P< 0. 01); the specific activity of lactate dehydrogenase and cytochrome oxydase rose up significantly (P < 0. 01) . 2) Compared with normal liver, the specific activity of lactate dehydrogenase and cytochrome oxydase on cancer bearing mice liver significantly rose up (P < 0 . 01), but, the succinate dehydrogenase had no significant change (P >0 . 05). The results indicated that one of the reasons of the strong glyucolysis in cancer cells may be because of the inhibition of TCA cycle, the high activity of oxydative phosphorylation seems to supply more energy to cancer cells. The results offer a support to establish a biochemical inspection for cancer disease by using the activity identification of lactate dehydrogenase and cytochrome oxydase.