Abstract: The kinds and activity of cellulase of 7 strains of dominant cellulose-degrading bacteria separated from healthy camel rumen were determined by using traditional determination method of cellulase activity 3, 5-dinitrosalicylic acid method （DNS） and self-constructed determination method of cellulase activity. The determination results showed that the activity of CX in different strains determined by DNS was 1#〉2#〉17#〉10#〉15#〉8#〉20#. And the activity of C1 was 1#〉2#〉17#〉20#〉10#〉15#〉8#. The activity ofβ-glucosidase was 1#〉2#〉17#〉10#〉20#〉8#〉15#. Total enzyme activity was 1#〉2#〉17#〉8#〉10#〉15#〉20#. It was seen from the determination results by the self-constructed method that the activity of CX in different strains was （1#、2#、15#）〉（10#、17#）〉（8#、20#）. And the activity of C1 was （1#、2#、15#、17#）〉（8#、10#）〉20#. The activity of β-glucosidase was （1#、2#、8#、10#、15#、17#）〉20#. Total enzyme activity was 2#〉1#〉15#〉17#〉10#〉8#〉20#. In conclusion, the enzyme activity determined by two methods was adjacent. But there were a great number of problems in the determination process by DNS method. And the self-constructed method could conquer the disadvantages of DNS method. The determination results of self-constructed method were simple and intuitive. And the determination results would be more accurate when the self-constructed method was combined with DNS method.