To inexpensively produce a press frame with high accuracy and rigidity while evading welding and prestress rods since, in the structural design of a press frame, the welding of composing parts and the adoption of prestress rods require great know-how for the assembly thereof.

In a press frame with a hexahedron shape composed of four side face plates composing front and rear-right and left and pressure receiving plates arranged parallel as a vertical couple, the insides of the side plates are provided with grooves with a width matching to the respective thickness of upper and lower pressure receiving plates parallel to the positions to be disposed with the upper and lower pressure receiving plates, and the four side faces of the upper and lower pressure receiving plates are suitable for the grooves of the side face plates, so as to compose a frame, thus a press frame ensuring all the parallels and right angles of the spaces of the six plates can be easily provided.