To make a hydraulic press machine used for cold forging, etc., light weight, compact and a structure enduring eccentric load.

A cylinder tube 20 is fixed on a frame 22 having roughly equal width with a bolt 23. A rod part 26 connecting to a cylindrical shape head part 24 of a piston 21 is made to a polygonal shape having a small diameter than the head part 24, an upper die 11 is mounted on a lower end face 27, facing side faces 28, 28 are made to a guide face. A slide 30 is arranged to the opening upper edge of the frame 22 and a lower die 12 is mounted on the bottom face. The piston 21 is slided downward with hydraulic pressure of a pressurizing chamber 14, a stock is press worked between the upper die 11 and lower die 12. Even when eccentric load is generated, the load is supported by sliding between the slide 30 and guide face 28, the piston 21 is precisely guided. A pressure force is transmitted to the cylinder tube 29 through the upper die 11, lower die 12, frame 22 and balanced with the upward force in the pressurizing chamber 14.