A hot water storage boiler comprising: a body having defined a space therein, to which water is supplied, the body comprising a combustion chamber provided in an upper portion of the space; a burner projecting a flame into the combustion chamber; a plurality of tubes located within the space, with top ends thereof being integrally connected to a bottom surface of the combustion chamber and bottom ends thereof extending to a bottom portion of the space; an exhaust unit provided on a bottom of the body and integrally connected to the bottom ends of the tubes; and a spray pipe disposed within the body to face the bottom surface of the combustion chamber, with a plurality of spray holes thereof being provided in a direction of the bottom surface of the combustion chamber, wherein water supplied to the spray pipe is sprayed through the plurality of spray holes toward the bottom surface of the combustion chamber, characterized in that wherein the spray pipe comprises: a plurality of C-shaped concentric supply pipes having different radii; a connector pipe connecting ends of a pair of adjacent supply pipes among the plurality of supply pipes, except for one end of an outermost supply pipe and one end an innermost supply pipe among the plurality of supply pipes; and an inlet pipe connected to one end of the outermost supply pipe or the innermost supply pipe among the plurality of supply pipes, and the plurality of spray holes is provided in top portions of the supply pipes and the connector pipe along longitudinal directions thereof, wherein water entering through the inlet pipe is supplied to the plurality of supply pipes and the connector pipe and then is sprayed through the plurality of spray holes toward the bottom surface of the combustion chamber, wherein the innermost supply pipe among the plurality of supply pipes is arranged to face a center of the bottom surface of the combustion chamber, and the outermost supply pipe among the plurality of supply pipes is arranged to face an outer periphery of bottom surface of the combustion chamber. a body having defined a space therein, to which water is supplied, the body comprising a combustion chamber provided in an upper portion of the space; a burner projecting a flame into the combustion chamber; a plurality of tubes located within the space, with top ends thereof being integrally connected to a bottom surface of the combustion chamber and bottom ends thereof extending to a bottom portion of the space; an exhaust unit provided on a bottom of the body and integrally connected to the bottom ends of the tubes; and a spray pipe disposed within the body to face the bottom surface of the combustion chamber, with a plurality of spray holes thereof being provided in a direction of the bottom surface of the combustion chamber, wherein water supplied to the spray pipe is sprayed through the plurality of spray holes toward the bottom surface of the combustion chamber, characterized in that wherein the spray pipe comprises: a plurality of C-shaped concentric supply pipes having different radii; a connector pipe connecting ends of a pair of adjacent supply pipes among the plurality of supply pipes, except for one end of an outermost supply pipe and one end an innermost supply pipe among the plurality of supply pipes; and an inlet pipe connected to one end of the outermost supply pipe or the innermost supply pipe among the plurality of supply pipes, and a plurality of C-shaped concentric supply pipes having different radii; a connector pipe connecting ends of a pair of adjacent supply pipes among the plurality of supply pipes, except for one end of an outermost supply pipe and one end an innermost supply pipe among the plurality of supply pipes; and an inlet pipe connected to one end of the outermost supply pipe or the innermost supply pipe among the plurality of supply pipes, and the plurality of spray holes is provided in top portions of the supply pipes and the connector pipe along longitudinal directions thereof, wherein water entering through the inlet pipe is supplied to the plurality of supply pipes and the connector pipe and then is sprayed through the plurality of spray holes toward the bottom surface of the combustion chamber, wherein the innermost supply pipe among the plurality of supply pipes is arranged to face a center of the bottom surface of the combustion chamber, and the outermost supply pipe among the plurality of supply pipes is arranged to face an outer periphery of bottom surface of the combustion chamber.