Disclosed herein are an illumination unit and an illumination system. The illumination unit includes a first reflector, a second reflector, a light source module arranged between the first reflector and the second reflector, and a supporting member for supporting the second reflector. The supporting member includes first and second inclined surfaces arranged adjacent to each other at opposite sides of an inflection point. The supporting member has a distance of 15 to 50 mm between a first horizontal line horizontally passing through the inflection point and a second horizontal line horizontally passing through an end of the first inclined surface or an end of the second inclined surface. The supporting member includes projections having asymmetrical side surfaces opposing each other. The height ratio between the side surfaces of the supporting member is 1:1.01 to 80 or 1.01 to 80:1.