A mold device of related art has a problem that a total volume of the device becomes large. In an example aspect of the present disclosure, a mold device includes a fixed mold base for supporting a fixed mold, a mobile mold base for supporting a mobile mold, a frame to which the fixed mold base is fixed, provided to extend in a direction in which the mobile mold base is moved, and formed into a wall shape, and holding means for movably supporting the mobile mold base to the frame. The frame is provided along at least one side of the mobile mold base except an upper surface thereof with the mold device installed, and the holding means support the mobile mold base at one side of the mobile mold base.

A mold device includes a frame that is a vertical wall having a first surface that is a vertical surface to which a holding mechanism is mounted and supported only by the first surface. A fixed mold base supporting a fixed mold, one surface thereof fixed to the first surface of the frame, and a mobile mold base supporting a mobile mold, the mobile mold base held by the holding mechanism so that the mobile mold base moves closer to and away from the fixed mold base. The holding mechanism includes a rail fixed to the first surface, and a guide fit on the rail in such a way that the guide moves on the rail while the guide is fixed to the mobile mold base. The mobile mold base is supported by the holding means without using a tie bar, and cantilevered on the first surface via the holding mechanism.