This study has finished the crankshaft fatigue strength test by the rational experimental method. And based on the experimental data, the statistical regression analysis of eight commonly used hypothesis distributions, namely Weibull (two-and three-parameter), normal, lognormal, extreme minimum value, extreme maximum value, and exponential (one-and two-parameter), are developed. Then the degree of fitting effect between the experimental data with the eight statistical distributions is evaluated. The result shows that six kinds of statistical distributions, including Weibull (two-and three-parameter), normal, lognormal, extreme minimum value, extreme maximum value, have good fitting effect. In all distributions, the best one is three-parameter Weibull distribution.