For two normal populations with unknown but equal variances or unknown variances but with large sample size, hypothesis test of the means has given a solution. But there is short of research for unequal variances with small sample size. To address the problem, the processing method of theoretical proof is put forward, and the realizing process and MATLAB program for realization are designed. Finally an actual case is used to illustrate the feasibility of the method. Compared with the situation of large sample, this method needs less samples.