A quick connector includes a socket having a socket opening and a plug inserted and coupled to the socket opening. The socket includes a socket body having a socket space into which the plug is inserted and a latch that hampers insertion of the plug into the socket space or stops the plug from escaping to the outside. The plug includes an insert body, an insert O-ring that surrounds the insert body, and an insert hook protruding outward from the insert body. The latch includes a latch frame, a latch opening formed in the latch frame, and a latch step that hides part of the latch opening, the latch step being disposed on the latch frame such that when the insert body is inserted into the socket space, the insert O-ring does not make contact with the latch step, but the insert hook makes contact with the latch step.