To provide a multifunction water stop cock for water supply capable of providing alert, agile, and secure operation at the time of return prevention and simplifying the exchange work of valve element packings when the valve element packing is worn.

A main body barrel 1 has a water stop cock chamber 2 and a check valve chamber 3. A ball cock body 4 is turnably provided in the water stop cock chamber 2, and a check valve element 11 is provided in the check valve chamber 3 so as to move vertically and freely. A back pressing force generated by a spring is applied to the check valve element 11 to energize it in the direction of valve closing. A ringlike groove 13 is provided on a lower end face of the check valve element 11, and a ringlike valve element packing 12 is fitted in this groove and is fixed by pressing it by a packing retainer 14.