In this investigation, one method that the parameter estimation of ultrasonic echo based on ant colony algorithm which is used for continuous function optimization was presented.According to asymmetrical Gaussian chirplet model, the basic principle and parameter estimation procedures of ant colony algorithm for parameters estimation application of ultrasonic echo are given in detail in this paper.The ultrasonic echo parameters under different signal to noise ratio(SNR) are estimated through the numerical simulation. The simulation results show that this method does not depend on the selection of the initial values and can search in a wider scope to obtain the globally optimal solutions, and has a higher precision.