The present invention provides a microwave oven. The microwave oven comprises a shell, a microwave generation device, a heating tube, a heating tube cover, an air duct, a fan and a door, wherein the heating tube cover is arranged on the top of the shell and is communicated with a cavity enclosed by the shell through an opening or a plurality of through holes formed on the bottom of the heating tube cover. The microwave generation device and the fan are arranged at one side of the shell. The heating tube comprises a first heating tube and a second heating tube, wherein the first heating tube is supported on the top of the shell through the heating tube cover. The second heating tube is arranged at the side of the shell. The air duct warps the heating tube cover and the first heating tube and the second heating tube from the outside. An opening at one end of the air duct is arranged at a positioning corresponding to the fan and the other end of the air duct is communicated with the other side of the shell. Part of wind blown out from the fan is blown into the heating tube through the air duct to bring the heat generated on the surface the heating tube cover and by the heating tube to a chamber of the oven through the top and sides of the shell to accelerate the air flow in the chamber of the oven and make the heat distributed evenly. And the top heating tube and the side heating tube can work independently and can be set in different states according to different food cooling equipments.