Abstract: A positioning correction method is proposed to solve the problem of decreased positioning accuracy caused by the hydrophone installation deviation in the multi-element ultra-short baseline positioning system of full-ocean-depth manned submersible. Based on the basic principle of ultra-short baseline positioning, the influence of the primitive installation errors in x and y directions on the positioning result is analyzed to improve the ultra-short baseline positioning accuracy. Using the above analysis results, a method combining phase correction and Toeplitz correction is proposed to improve the positioning accuracy. Simulation and experiment show that the proposed algorithm is simple, easy to implement, and effective, and can effectively improve the positioning accuracy.