The invention discloses a method and device for depth domain velocity modeling in a desert area. The method comprises the following steps that a shallow superficial depth domain velocity model is established; a middle and deep depth domain velocity model is established; velocity fusion of the shallow superficial depth domain velocity model and the middle and deep depth domain velocity model is conducted to obtain a shallow, middle and deep integrated depth domain initial velocity model; and the shallow, middle and deep integrated depth domain initial velocity model is updated iteratively by using an isotropic tomography velocity inversion technology and anisotropy tomography velocity inversion technology. According to the method for depth domain velocity modeling in the desert area, a high-precision depth domain velocity model of the desert area can be obtained, and imaging quality of high-depth migration can be further improved.