A valve connector for medical lines includes a tubular body having a male inlet fitting with external luer cone, which can be coupled to a female tubular fitting with internal luer cone, wherein the inlet fitting includes an internally threaded external tubular element for screwed engagement with the female fitting, and an internal tubular element that can be displaced axially from a retracted position of closing to an advanced position of opening of the valve means that control the passage of flow through the connector. The internally threaded external tubular element is free to turn, and the arrangement is such that, when it is screwed off the female fitting and the passage of flow is closed by the valve means, the external luer cone and the internal luer cone remain axially coupled to one another by friction.
