The invention discloses a thermal storage water heating system and a heating mode. At night, water in a thermal storage water tank is heated by a valley electricity boiler; in the day time, water in the thermal storage water tank is heated by a vacuum tube solar water heater or the waste heat of drying room exhaust gas in a fine day, and water in the thermal storage water tank is heated by the valley electricity boiler or the waste heat of drying room exhaust gas in a cloudy day. The thermal storage water heating system fully utilizes cheap energy, heats thermal storage water at different times, has high controllable performance and simple equipment, and can be independently switched to small circulation by an electric hot-water boiler to heat a heat exchanger by the boiler, thus economically and quickly heating workpieces. The thermal storage water heating system has wide use range, is suitable for large and small scale enterprises in, such as foundry industry, manufacture industry, processing industry, electrofacing industry, medicine industry, heat treatment and the like, and is also suitable for supplying heat for small and medium scale enterprises.