PURPOSE: To facilitate connection by internally inserting a stop cock and a guide pipe, over which a packing is set, into a water-supply delivery pipe under the state of water discharge and connecting the stop cock and the water-supply delivery pipe while making water escape into the guide pipe.

CONSTITUTION: A guide pipe 10 is inserted to a new stop cock 1 while a packing 2 is inserted from the front end of the guide pipe 10. The connecting box nut 4 of a water-supply delivery pipe port is removed, and an old stop cock is taken away. Water is ejected from the water-supply delivery pipe port at that time, but the state, in which the front end of the pipe 10 is inserted quickly to a feed pipe and water is made to escape into the pipe 10, is brought, and water is not injected near a connecting section. The nut 4 is screwed to the screw section of the stop cock 1, and the stop cock l and the water-supply delivery pipe are coupled. The pipe 10 is extracted, the knob of the stop cock 1 is turned, and the state of cut-off is brought. Accordingly, the stop cock can be connected easily and rapidly without requiring skill, and can also correspond to the water injection pressure of a large-bore piping.