To provide a method for supplying water to a boiler of a coke dry quenching installation, by which cooling temperature to a cooling tower can be lowered with a low cost installation without causing dew condensation corrosion, and to provide a facility for supplying water.

The method for supplying water to the boiler of the coke dry quenching installation, comprising charging red-hot coke into a cooling tower 1, blowing an inert gas into the cooling tower 1 to exchange the heat, delivering the heat-exchanged inert gas into the boiler 4, exchanging the heat of the delivered inert gas with the heat of cooling water supplied from the water supply tank 12 to the boiler 4 to recover the waste heat, and then returning and recycling the recovered inert gas to the cooling tower 1, is characterized by supplying the cooling water from the water supply tank 12 to a deaerator 16 to subject the cooling water delivered from the deaerator 16 and the cooling water supplied from the water supply tank 12 to the deaerator 16 to a heat exchange, and then supplying the heat-exchanged cooling water delivered from the deaerator 16 to the boiler 4.