Ready assembled/disassembled support board structure for drawers, including a cabinet body and two support boards. The cabinet body is a rectangular body formed by five rectangular wall boards defining an interior space and a front opening. Several drawers are vertically arranged in the cabinet body. The support boards are respectively disposed on the inner faces of the side walls of the cabinet body. Several cabinet body slide rails are disposed on the support board to be assembled with the drawer slide rails of the drawers. A first stop section is disposed on a predetermined portion of the cabinet body. The support board includes a second stop section and a resilient section. The second stop section is disposed on the support board corresponding to the first stop section for abutting against the first stop section. The resilient section is disposed on the support board opposite to the second stop section for abutting against a predetermined portion of the cabinet body.