Abstract: A microwave oven includes an oven seat, an oven cover hinged on the oven seat and a cooking chamber enclosed by the oven seat and oven cover. The oven cover comprises, in this order from an inner side to an outer side, a waterproof cover, a microwave shielding cover and an outer cover that are formed respectively in a hemispherical shape and assembled together via an oven cover skeleton and a skeleton frame. The oven cover skeleton includes an annular base body with an assembly groove to allow the waterproof cover to be wedged therein. The waterproof cover has a first flange to be wedged in the assembly groove. The microwave shielding cover has a second flange to be pressed on the base body. The skeleton frame is coupled on the outer side of the microwave shield cover and pressed on the second flange and oven cover skeleton.