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