Abstract: The array shape calibration of a flexible horizontal array deployed on the sea-bottom can be solved by measuring the sound propagation delay difference between the array elements with two auxiliary sources. The traditional algorithms only measure the time delay difference between adjacent array elements, and the error will accumulate with the increase of noise. However, the proposed method in this paper can effectively reduce the accumulation of errors through redundant time delay measurement when the signal to noise ratio decreases, therefore the accuracy and stability of array-shape calibration can be improved. Numerical simulation and experiment results both verify the effectiveness of the method.