A ceiling fan having double-layer blades includes a motor unit, a blade frame unit, a first blade unit, and a second blade unit. The blade frame unit has a blade frame body. The first blade unit includes a plurality of first blades. The second blade unit includes a plurality of second blades. The first blades and the second blades surround the outside of the blade frame body, so that there is no need for the motor unit to provide a motor housing for connecting the first blades and the second blades, thereby saving costs and installation costs. With the arrangement of the first blades and the second blades, the ceiling fan can increase the current of air for cooling.