Abstract: Time delay estimation as a target location technology has been widely applied in all sorts of fields. However, its estimation precision was affected by various factors and then this limited the accuracy of location. Therefore, this article mainly aimed at limited sampling rate and noise effect, put forward a kind of high accuracy time delay estimation algorithm. The algorithm on the basis of the correlation peak precise interpolation method, used second correlation and Hilbert difference to improve itself. The simulation results show that this algorithm not only improves the resolution of correlation function but also has strong anti noise performance and peak detection ability. It can get fairly accurate time delay estimation value under high SNR environments and can improve time delay estimation performance significantly under low SNR environments. Therefore, the algorithm proposed by this paper is a kind of effective method to estimate time delay accurately.