A coupling part for a plug connector arrangement is provided. The coupling part having a coupling body comprising a receptacle into which a plug-in part can be plugged into in the direction of a longitudinal axis of the receptacle, in order to produce a fluid-tight connection. The coupling part has two spaced-apart locking elements which, in a locking position, penetrate laterally, opposite one another, into the receptacle in order to engage behind the plug-in part and which can be moved into a release position in order to release the plug-in part. A spring element is integrally formed with and connects the locking elements together. In order to develop the coupling part so that it is easier to handle, the coupling part is provided with an actuating element which is adapted to be moved relative to the coupling body. Movement of the actuating element causes the locking elements to be moved out of the locking position into the release position, in which they are spaced apart from one another to a greater extent than in the locking position.