A light flux controlling member has: a light control/emission surface that controls a traveling direction of light; a concavity that allows a main beam to be incident inside; and a back surface that extends in a radial direction from an opening rim part of the concavity and that allows sub-beams to be incident inside. One of a grid convex part which arranges a plurality of strips of convex parts in a grid pattern and a grid concave part which arranges a plurality of strips of concave parts in a grid pattern is formed in the back surface of the light flux controlling member.