The present invention discloses a multi-aperture depth migration imaging method, device and system. The method includes the following steps that: a migration aperture is decomposed into a plurality ofsub-apertures, and multi-aperture parameters are determined; a shot-geophone center point in each seismic record is determined; a horizontal distance from each imaging point to the shot-geophone center point of each seismic record is obtained, and the maximum aperture of a depth where the corresponding imaging point is located is obtained; the serial number of an aperture where each imaging pointis located is obtained according to the multi-aperture parameters and the horizontal distance from each imaging point to the shot-geophone center point of each seismic record; and when the horizontaldistance from each imaging point to the shot-geophone center point of each seismic record is smaller or equal to the maximum aperture of the depth where the corresponding imaging point is located, anaperture weight function is determined according to the multi-aperture parameters; imaging energy is weighted through the aperture weight function according to the serial numbers of the apertures, and the weighted imaging energy is arranged in the sub-apertures, and imaging values in the sub-apertures are obtained; and a multi-aperture depth migration imaging data body is obtained through using the imaging values in the sub-apertures.