A press machine is provided that can accurately detect load acted on a frame. A frame 1 includes an upper horizontal frame 1b, a lower horizontal frame 1a, and a vertical frame 1c arranged to connect the upper horizontal frame 1b and the lower horizontal frame 1a. A press drive mechanism 8 is provided to the upper horizontal frame 1b. A strain generation member 23 is arranged across from the upper horizontal frame 1b to the vertical frame 1c. In the strain generation member 23, an intermediate portion 23a has a cross-sectional area that is smaller than those of end portions 23b, 23c fixed to the upper horizontal frame 1b and the vertical frame 1c, respectively. A strain amount detecting body 24 is attached to the intermediate portion 23a of the strain generation member 23 in order to detect a strain amount.