With the aim to improve the efficiency and the coverage rate of the software testing,the generation methods of the test cases are researched.On the basis of the test methods such as equivalence classifications,this paper presents a technique to divide the interface parameters into two types,environment parameters and state parameters.Then,the effect of two different parameters with different characters on the generation of testing cases is analyzed and their algorithm models are established respectively.According to all of these,the reducible test cases are generated by fusing their functions in practice.Experimental results show that the test cases generated by the proposed method is one fifth as high as those of traditional generation methods at the same coverage rate,which reaches the purpose of covering more test demands with fewer test cases.