The invention relates to a new energy vehicle water-cooling motor shell manufacturing process and its structure. The water-cooling motor shell manufacturing process is reasonably designed and is capable of increasing the various performance parameters of the water-cooling motor shell. According to the invention, after eleven steps of processing and manufacturing referred to as from (a) to (k), the water-cooling motor shell is characterized by its stable and reliable structure, absence of casting defects and residual sand cores in spiral waterway and up-to-scratch hardness. Therefore, the service life time of the water-cooling motor shell is increased and the actual utilization need can be met.