AIM To creative of the methods of the content determination of Diclofenac Zn, and inspect the stability. METHODS The determination of Dicclofenac Zn was established by spectrophotometrey; The stability of Diclofenac Zn was studied by hypertemperature experiment, high humidity experiment and acceleration experiment. RESULTS The content of Dic zn is changed from 95.95% to 99.02%. The stability experiment′s result concidences the require of CHP . Conclusions: The content of Dic zn is high,the stability of Dic zn is good.