Connecting Device for Infusion Line

The object is to keep a portion in the vicinity of a liquid discharge port in a clean state even at the time of priming or connection and to enable easy connection and disconnection of an infusion line without causing leakage of liquid from the liquid discharge port even when connection is released. This is solved by a tube ( 2 ) that forms a flow channel of a male connector ( 1 ) and is provided at its distal end portion ( 4 ) with a gas discharge portion ( 7 ) that blocks discharge of liquid and allows discharge of gas from the flow channel, a liquid discharge port ( 8 ) that allows discharge of liquid, and at a periphery of its distal portion ( 4 ) with shutter means ( 20 ) which opens the liquid discharge port ( 8 ) by a pressing force received from a male connector ( 30 ) when connected and restored to close the liquid discharge port ( 8 ) when the pressing force is released.