Aimed at the generation of high-quality test set in the shortest possible time, the test generation for combinational circuits (CC) based on the chaotic particle swarm optimization (CPSO) algorithm is presented according to the analysis of existent problems of CC test generation, and an appropriate CPSO algorithm model has been constructed. With the help of fault simulator, the test set of ISCAS 85 benchmark CC is generated using the CPSO, and some techniques are introduced such as half-random generation, and simulation of undetected faults with original test vector and inverse test vector. Experimental results show that this algorithm can generate the same fault coverage and small-size test set in short time compared with other known similar methods, which proves that the proposed method is applicable and effective.