Abstract: By using the method of structural pattern recognition, multistage sequence of equal-string form is built. By transforming and analyzing history data of stock market, examining the probability of payoff or loss, a new analysis method of securities investment is established, namely equal-string form combination predicted method. By this prediction method, the lag and the uncertainty of traditional analysis can be remedied partly, the relevant parameter to consistent with the movement of market can be adjusted immediately, and the success ratio of forecast can be also heightened. In the meanwhile, computer can easily recognize it.