Objective To investigate a new method of measuring serum total protein by improving biuret double reagent through two point terminal method in order to dissolve the sample's interference of hemolysis, icterus, lipid , polymeric glucose.Methods The precision, recovery rate, the examination limit, the linear scope and the interference experiments were done by improving biuret reagent in order to ensure the method's basic function. The method was compared to Doumas method in order to ensure its reliability and the effection of dissolving the interference.Results The proportion of sample and reagent was 5∶220 ?l and the linear scope was 140 g/L. Regress equation:Y=484.0+48.06X,r=0.999 3.The within run CV(n=20) was 0.24% and the day to day CV(n=20) was 1.07%.The average recovery rate was 99.5%(95.6%~103%).The examination limit was 2.36 g/L. The interference was not significant when Hb concen tration was lower than 2.1 g/L, Bil lower than 148 ?mol/L,TG lower than 28.2mmol/L and polymeric glucose lower than 30 g/L. While measuring normal sample, improving method and Doumas method were highly correlation. Regress equation:Y=-2.435 4+1.037 4X,r=0.988 2. There wasn't a significant reference between results.Conclusion It could dissolve effectively the sample's interference of hemolysis, icterus, lipid, polymeric glucose and increase the result's accuracy while adopting improving biuret double reagent through two point terminal method.