Abstract: In order to reduce the storage requirements of test data and test application time, a BIST scheme based on the theory of folding computing is proposed for multiple scan chains.Firstly, test pattern is horizontally compressed using the input reduction technique, and so the compatible scan chains are designed for broadcasting test data during testing.Secondly, the test set is vertically compressed into a seed set based on the theory of folding computing, and so adjoining test vectors of the same folding seed only differ in one bit position and are shifted into multiple scan chains in parallel during testing.Experiment results on ISCAS benchmark circuits demonstrate the average test compression rate of the proposed scheme is 95.07%, and the average test application time is 13.35% of the previous scheme.