A cross flow fan includes a fan frame and a rotor having a hub, a shaft connected with the hub at its rotation center, a plurality of blades, and a disk structure connected with the blades and hub within the fan frame. The fan frame has a frame wall having a lateral flow inlet to the rotor and a lateral flow outlet from the rotor, a base carrying the rotor and frame wall, a cover on one side of the frame wall opposite to the base, and a partition structure disposed between the blades and an inner wall surface of the frame wall. A normal line of the lateral flow inlet and a normal line of the lateral flow outlet are not parallel to an extension direction of the shaft. The blades directly face the lateral flow inlet and the lateral flow outlet along radial directions of the shaft.