A method for assembling a camera module includes arranging a first sub-lens assembly and a photosensitive assembly on an optical axis of a second sub-lens assembly to form an optical system capable of imaging. The method includes increasing an actual measured resolution of imaging of the optical system to a first threshold by adjusting a relative position of the first sub-lens assembly with respect to the second sub-lens assembly. The method includes decreasing an actual measured image plane inclination of imaging of the optical system, obtained by using the photosensitive element, to a second threshold by adjusting an angle of an axis of the photosensitive assembly with respect to a central axis of the second sub-lens assembly. The method includes connecting the first sub-lens assembly, the second sub-lens assembly, and the photosensitive assembly. A corresponding camera module is also included.