Abstract: Regression equation between Brinell hardness and ultimate strength of ZG06Cr13Ni4Mo stainless steel material was gained to be HBW=0.326 9Rm according to the statistic analysis on large tensile and hardness test data. Significance level of the regression equation was proved to be high based on the results of hypothesis test statistics F>Fcritical, probability P<0.05, and it could be applied to predict the Brinell hardness through the ultimate strength of ZG06Cr13Ni4Mo stainless steel material in some definite accepting interval. The study provided reference for the actual hardness test and judgment test accuracy.