A mold for in-mold decoration comprises a stationary-side mold (2, 102) and a movable-side mold (1, 101), at least one of the molds having a cavity-forming block (3, 21, 121, 131) including a molding-use cavity (28, 58, 128, 138) and a dieset (7, 10, 107, 110) for mounting the cavity-forming block. The dieset (7, 10, 107, 110) for mounting the cavity-forming block comprises a mounting face (7a, 10a, 107a) which is positioned on a face opposed to the other mold, and a mold clamping force-receiving portion (6a, 6b, 112a, 112b) for receiving a mold clamping force between the closed molds. The mold further comprises a clamp (9, 109) in the movable-side mold (1, 101) for retaining the decorating film (13) in a state that a design pattern (221) of a decorating film (13) is positioned inside the molding-use cavity (28, 58, 128, 138), the clamp (9, 109) being supported by the cavity-forming block (3, 103) of the movable-side mold (1, 101) or by the mold clamping force-receiving portion (6a, 112a) of the movable-side mold (1, 101).