A light-diffusing sheet includes a transparent film and a light-diffusing layer formed on at least one side of the transparent film. The transparent film contains a thermoplastic resin having a substituted and/or non-substituted imido group in a side chain, and a thermoplastic resin having a substituted and/or non-substituted phenyl group and nitrile group in a side chain, and the surface with the minute unevenness has an average height-depth spacing (Sm): Sm.ltoreq.80 .mu.m, a center-line average surface roughness (Ra): Ra.ltoreq.0.25 .mu.m and a ten-point average surface roughness (Rz): Rz.ltoreq.9Ra.