To provide a flexible light guide plate capable of retaining a small color difference between an incident light color and emitting light color over a long period from initial time, excellent in light source color reproducibility, allowed to efficiently and uniformly emit light, allowed to be used in a state bent to an optional shape because of sufficient flexibility, and further capable of securing excellent illuminance.

A flexible light guide plate includes a tabular light guide layer composed of thermosetting polyurethane and having flexibility and diffusion means for diffusing light made incident into the light guide layer. The thermosetting polyurethane is obtained by thermally setting at least one sort of polyol component selected from a group consisting of polyether polyol, polycaprolactone polyol and polycarbonate polyol, an aliphatic polyisocyanate component and a hardening agent under existence of a non-amine catalyst.