Abstract: According to threshold de-noising algorithm to select the problem of proper threshold, this paper put forward a self-optimizing algorithm of optimal threshold. This paper discusses the optimum threshold concept and the optimum threshold is decided by signal and threshold function. Based on this concept, this paper provides the optimal method concrete steps, optimization method discrete threshold from zero to final value and from these discretization threshold can be found the optimal threshold. However, large calculated amount become the problem of the method. Based on this problem, this paper gives the solvable methods and proves it. Through the dead value of high frequency phenomenon that is observed by experiment fix the final value, and through single peak phenomenon and multi-resolution analysis simplify the method. Experiments show that the proposed method improves the signal-to-noise ratios and reduce the root mean square error. Moreover, the de-noising signals have smooth and visual appearance.