Eighteen heads of F₁ of Limusin and Pasture red cattle were used to test the activity of five kinds of plasma enzyme,i.e.GOT,GPT,Amy,LDH,AKP.Correlation existed in different degrees among activity of the five enzymes and beef traits,such as kidney fat,ratio of carcass meat,ratio of meat to bone,eye-muscle area and marbling score.According to the results of regression,GPT may be used to select ratio of carcass meat and ratio of meat to bone,while GOT may be used to select eye-muscle area.