A fan includes a plurality of blades and a motor. The motor includes a hub and a shaft having an end connected to the hub, a bushing, a bearing, and an oil-sealing structure. The blades are connected with and surrounding around the hub. The bushing is for supporting the other end of the shaft, and the bearing is disposed in the bushing and used to telescope the shaft. The shaft passes through the oil-sealing structure. The oil-sealing structure is telescoped to the shaft to fit tightly and the oil-sealing structure includes a main body and a barricade inwardly extending toward the shaft so that the oil-sealing structure is fixedly connected with the bushing.