The diffraction of a plane shock wave at a convex corner with a sharp edge was studied both experimentally and numerically, and the shape of the diffracting shock wave was classified into four different types according to the profiles of wall shocks. The domains and transition boundaries of these four types were shown in an incident shock Mach number‐diffraction angle plane. The flow field behind the diffracting shock wave was also investigated in the present experimental and numerical studies, and the characteristics of the second and the third shock waves which appeared in this perturbed region were discussed.