Blood sugar contents of three hundred and thirty blood specimens were determined by six different analytical methods, i.e., the glucose-oxidase method (G), the autoanalyser method with Hoffman's method (A), the Somogyi-Nelson method (S), the o-toluidine method (T), the Momose's method (M) and the Hage-dorn-Jensen method (H). The values determined by micromethods of Hagedorn-Jensen, of Momose and of Somogyi-Nelson are usually higher, and the values obtained by o-toluidine method are mostly lower than those estimated by the glucose-oxidase method. The values determined by the autoanalyser method are most consistent with those of the glucose-oxidase method among the five analytical methods. With the values of six series, the regression equations were obtained as following: A=0.86 G + 13, S=0.90 G + 34, T=0.76 G + 8, M=0.98 G + 28, H=0.85 G + 40, S=1.02 A + 23, T=0.88 A-3, M=1.10 A + 17, H=0.98 A + 26, T=0.75 S-7, M=0.99 S+4, H=0.83 8+23, M=1.22 T+24, H=0.78 M+26.