A method for detecting random access of user equipment, applicable to a mobile communication system consisting of at least one base station and a group of UEs, wherein the said BS and the said group of UEs use a set of N orthogonal or quasi-orthogonal pseudo-random sequence codes for the random access of UE, wherein N is a positive integer, and by detecting the pseudo-random sequence code selected by each randomly accessed UE, BS implements a simultaneous detection of the random access of UEs, the method comprising: A. BS making a correlation operation of the random access signal received at one moment from UE containing information of the pseudo-random sequence codes selected by the accessing UE with a pseudo-random sequence code from the local pseudo-random sequence code set of the BS, and obtaining a corresponding correlation result window, wherein the said correlation operation starts from any pseudo-random sequence code of the pseudo-random sequence code set and ends when operations with all the N pseudo-random sequence codes are completed; B. finding the maximum correlation peak value point in every correlation result window; characterised in steps of: C. based on the position of each correlation peak value point, finding a correlation peak window in the corresponding correlation result window, or finding a correlation peak window and the front-side and rear-side windows at both sides of the correlation peak window in the correlation result window; wherein, the correlation peak window refers to a window with a first predetermined length which contains the correlation peak value point and several adjacent value points; the front-side window refers to a window with a second predetermined length, the front-side window is at the front of the correlation peak window; and the rear-side window refers to a window with a third predetermined length, the rear-side window is at the rear of the correlation peak window; D. performing preset calculations on the correlation results in every correlation peak window or every correlation peak window and its front-side and rear-side windows, determining whether each process result is larger than its corresponding predetermined threshold, if each calculation result is larger than its corresponding predetermined threshold, determining that the pseudo-random sequence code taking part in the correlation operation in Step A is the pseudo-random sequence code selected by a UE accessing at that moment. A. BS making a correlation operation of the random access signal received at one moment from UE containing information of the pseudo-random sequence codes selected by the accessing UE with a pseudo-random sequence code from the local pseudo-random sequence code set of the BS, and obtaining a corresponding correlation result window, wherein the said correlation operation starts from any pseudo-random sequence code of the pseudo-random sequence code set and ends when operations with all the N pseudo-random sequence codes are completed; B. finding the maximum correlation peak value point in every correlation result window; C. based on the position of each correlation peak value point, finding a correlation peak window in the corresponding correlation result window, or finding a correlation peak window and the front-side and rear-side windows at both sides of the correlation peak window in the correlation result window; wherein, the correlation peak window refers to a window with a first predetermined length which contains the correlation peak value point and several adjacent value points; the front-side window refers to a window with a second predetermined length, the front-side window is at the front of the correlation peak window; and the rear-side window refers to a window with a third predetermined length, the rear-side window is at the rear of the correlation peak window; D. performing preset calculations on the correlation results in every correlation peak window or every correlation peak window and its front-side and rear-side windows, determining whether each process result is larger than its corresponding predetermined threshold, if each calculation result is larger than its corresponding predetermined threshold, determining that the pseudo-random sequence code taking part in the correlation operation in Step A is the pseudo-random sequence code selected by a UE accessing at that moment.