Objective To explore the feasibility of lithium heparin anticoagulant plasma instead of serum in biochemical test . Methods 54 biochemical indexes were comparatively detected in 100 samples of lithium heparin anticoagulant plasma and serum . Results The detection results of 45 biochemical indexes in 100 samples of lithium heparin anticoagulant blood plasma and serum showed no statistically significant differences (P>0 .05) .There were statistically significant differences in the indexes of total pro-tein(TP) ,potassium ion(K+ ) ,lactic dehydrogenase(LDH) ,glucose(GLU) ,creatine kinase-MB(CK-MB) and lipase(LPS) between lithium heparin anticoagulant plasma and serum(P<0 .05) ,while results showed good correlation(the maximum r value was 0 .998 , the minimum r value was 0 .887);3 indexes of transferrin(TRF) ,α-L-fucosidase(AFU) and leucine aminopeptidase (LAP) had statistically significant differences (P<0 .05) and showed no correlation(r<0 .6) .Conclusion Lithium heparin has the strongly an-ticoagulant ability with the advantages of non-influence on cell volume and no hemolysis ,which can be used for routine biochemical test ,especially suitable for the outpatient service ,emergency and the patients with blood coagulation dysfunction ,but the detection of TRF ,AFU and LAP can not be suitable .