The invention provides a water-
cooling pipe, a motor housing and a manufacturing method thereof. The motor housing comprises a housing body and a water-
cooling pipe, wherein the water-
cooling pipe is arranged in the housing body; the water-cooling
pipe comprises two ports; the housing body comprises an inlet and an outlet; the two ports of the water-cooling
pipe are arranged at the inlet and the outlet respectively; the water-cooling
pipe is in a spiral form and is made of a
copper material; and at least one support body is arranged between
copper pipes of the water-cooling pipe. The manufacturing method of the motor housing comprises the following steps: (1) installing the spiral water-cooling pipe between a left
metal die and a right
metal die; (2) preheating the water-cooling pipe to 300-350 DEG C; (3) heating aluminum to 700-850 DEG G, and then adding 6.5%-7.5% of Si, 0.2%-0.4% of Mg and 0.03%-0.07% of La to obtain a molten aluminum
alloy; (4) filling a mold cavity between the left
metal die and the right metal die with the molten aluminum
alloy, wherein the
casting temperature is 700-720 DEG C; (5) after the molten aluminum
alloy is hardened, separating the left die from the right die and obtaining a motor housing blank; and (6) carrying out
artificial aging treatment on the motor housing blank.