A data optimization method and an integral prestack depth migration method are provided, including acquiring a target matrix to be optimized; generating a first sequence according to the target matrix; rarefying the first sequence according to a preset grid density to obtain a value position of each element of a second sequence, and working out a value of each element of the second sequence on the basis of the principle of least squares; performing interpolation on the second sequence to obtain a third sequence; calculating a target matrix corresponding to the third sequence; calculating an error between the target matrix to be optimized and the target matrix corresponding to the third sequence; recording, when the error is less than the first error threshold, the target matrix corresponding to the above second sequence as an optimized target matrix of the target matrix to be optimized.