Medical gas cylinder valve

The invention discloses a medical gas cylinder valve which comprises a valve body. A pressing cap is installed at the top end of the valve body, a valve rod penetrates through the pressing cap to stretch into the valve body, the valve rod is in threaded connection with the valve body, a sealing flat pad is arranged between the pressing cap and the top of the valve body, a check ring and a first O-shaped ring are arranged between the bottom end of the valve rod and the inner wall of the valve body, the outer wall of the bottom end of the valve body is sequentially sleeved with a second O-shapedring, a flat gasket and a third O-shaped ring from top to bottom, the valve body is provided with an air inlet and outlet channel and a pressure relief channel communicating with the air inlet and outlet channel, a pressure relief device is installed in the pressure relief channel, and an inner square hole is formed in the top end of pressing cap. The medical gas cylinder valve in the design is good in sealing effect and