Abstract: A quick connection-release coupling according to the present invention comprises a female coupling part having a cylindrical adapter and a male coupling part having a cylindrical nipple, a resiliently expandable and retractable C-shaped spring ring being arranged along an inner circumferential surface of the adapter, the nipple having an engaging portion protruded on an outer circumferential surface thereof, and the engaging portion being capable of being engaged with or disengaged from said C-shaped spring ring. A cylindrical releasing jig being movable forward and backward against the engaging portion is threadably arranged on the outer circumferential surface of the nipple. When pulling the nipple out of the adapter, the releasing jig is moved forward and pushes the C-shaped spring ring using an advancing force of the thread, thereby radially expanding the C-shaped spring ring to cause the engaged state between the engaging portion and C-shaped spring ring to be released.