An integral confined water source hot water supply system comprises a waste hot water tank, a main machine, a hot water storage tank, a tap water inlet pipe, a manual water supply pipe, a manual watersupply valve, an overflow port, an overflow water pipe, a blowdown pipe, a blowdown valve, a wastewater source circulation pipe, a preheated water inlet pipe, a water supply electromagnetic valve, ahot water conveying pipe, a hot water supply pipe, a waste hot water recovery pipe, a desander, a grease trap and a filter. The waste hot water tank is provided with the overflow port. Through the system, low heat in recovered waste hot water is transferred into tap water, and the problems that traditional hot water supply systems are low in heat recovery rate, and heat energy is wasted are solved.