The invention relates to a new energy vehicle water-cooling motor casing manufacturing process and a structure thereof; the structure comprises an inner casing, a first casing, and a second casing; the inner casing is in a cylindrical form structure; a storage chamber is arranged in the inner casing; the outer surface of the inner casing is provided with a plurality of outer rings; a water channelis arranged between adjacent outer rings, and provided with a port; channels of two adjacent water channels are arranged heat to tail; the first casing and the second casing are arranged outside theinner casing. The new energy vehicle water-cooling motor casing manufacturing process and the structure thereof are provided; the first casing and the second casing are assembled outside the inner casing so as to form the water-cooling motor casing; the design is simple in process; the structure is stable and reliable, and has no casting defect; the spiral water channel has no residual sand core,and the hardness satisfies requirements, thus prolonging the water-cooling motor casing service life, and satisfying real usage demands.