Illumination apparatus

An illumination apparatus, comprising:

• a housing, having an accommodation, a plurality of inlets, and a plurality of outlets, wherein the accommodation communicates with the outside of the housing through the inlets and the outlets;
• a light source, disposed in the accommodation;
• a centrifugal fan, disposed in the accommodation;
• and
• a heat sink, disposed in the accommodation, the heat sink comprising a base and a plurality of fins connected to the base, wherein the base is connected to the light source, the fins radially surround the centrifugal fan, an air channel is disposed between two adjacent fins, and the inlets and the centrifugal fan are arranged so that an air from the outside of the housing is capable of flowing into the accommodation through the inlets and then into the centrifugal fan in an axial direction of the centrifugal fan, and flowing out of the accommodation in a radial direction of the centrifugal fan through the air channel and the outlets.