The invention provides an aliasing noise suppression method and an aliasing noise suppression device. The method comprises the steps of performing dynamic correction on aliasing data; carrying out median filtering on data after being subjected to dynamic correction by adopting a specified step size; performing inverse dynamic correction on data after being subjected to median filtering, and obtaining first data; extracting effective signals from residual data based on the threshold denoising method of a complex curve domain, so as to obtain second data; adding the first data and the second data to obtain effective data; determining first pseudo-separation data of the aliasing data, and obtaining second pseudo-separation data of the effective data according to a preset aliasing operator; determining the difference value of the first pseudo-separation data and the second pseudo-separation data; adopting the difference value as new aliasing data, calculating to obtain a new difference value through iterative calculation, adding the effective data and the new difference value to obtain new effective data, repeating the above process in the same way until effective data obtained by thecurrent iteration meets a preset signal-to-noise ratio. According to the invention, the suppression effect and the suppression efficiency of the aliasing noise can be improved.