A rotatable illumination system includes a base and an illumination apparatus. The base includes a first housing, a rotating axis, a first brush and a second brush. The illumination apparatus includes a second housing, at least one light source, and a first electrode set. The second housing includes a bottom portion fixed to the rotating axis. The light source is disposed on the second housing. The first electrode set is disposed on the outer surface of the bottom portion. The first electrode set includes a first outer annular electrode and a first inner annular electrode electrically insulated from the first outer electric disc. The first brush electrically contacts with the first outer annular electrode and the second brush electrically contacts with the first inner annular electrode. The first outer annular electrode and the first inner annular electrode electrically connect with the light source, respectively.