An electrical plug connector based on the push-pull system, with a plug component and a matching plug component that can be connected to the plug component, both of which each include one or several associated electrical contacts held by a contact carrier, and with a locking mechanism that is provided on the plug component and includes at least one movable locking element with a latch surface that is associated, on the matching plug component, with a fixed locking element with a matching surface for the latch surface. The plug component includes a plug component housing with an axially displaceable sliding sleeve with an actuation element for the locking element formed on the inside wall, wherein, when the plug component is connected to the matching plug component, a—in the plug-in direction—frontal section of the circumferential wall area of the plug component housing overlaps the matching plug component on the outside in a plug-in area. The locking element projects radially beyond an inner surface of the circumferential wall area, and the locking of the locking element with the matching locking element is achieved by moving the locking element transversely to the plug-in direction of the plug connector along the circumferential wall area.