A medical push button valve having a valve housing, a flow channel formed in the valve housing as well as a valve piston which is arranged displaceably in the valve housing between a position releasing the flow channel and a position closing the flow channel. The valve piston is operatively connected with a pressure element mounted on the valve housing and is spring-loaded via at least one spring element. The valve piston is biased into the position closing the flow channel with the spring-loaded pressure element. In order to provide a medical push button valve which allows for a simple and fatigue-free one-handed operation, the spring-loaded pressure element can be locked in at least one position in which the valve piston operatively connected with the pressure element at least partially releases the flow channel.