A connector of a self-priming IV set valve including a connector body having a hollow region, and a valve element that is at least partially positioned in the hollow region that is configured to be moved, displaced or punctured by a cap that is releasably connectable to the connector body. When the cap is mounted to the connector, the cap either punctures or moves the valve element and a passageway is formed in the connector such that air and liquid are permitted to pass through the connector and into the cap. When the cap is not mounted to the connector, the valve element of the connector is configured to open under pressure to permit the passage of liquid through the connector and close when pressure ceases.