The invention relates to a household multifunctional water saving system, which comprises a water heater. A water inlet pipe B is connected to the lower end of the water heater; a water inlet pipe A and a water outlet pipe A are connected in the middle part of the water inlet pipe B; a PLC (Programmable Logic Controller) is arranged on the water inlet pipe B; a switch B is arranged below the PLC; a switch A is arranged above the PLC; a shower nozzle is connected to the end part of the water inlet pipe B; a switch C is arranged on the lower end of the water inlet pipe A; a constant temperature oven is connected to the upper end of the water inlet pipe A; a solenoid valve is arranged on the lower end of the water outlet pipe A; a water storage tank is connected to the end part of the water outlet pipe A; a water outlet pipe B is connected to the left side of the water storage tank; a water faucet is connected to the left side of the water outlet pipe B. The household multifunctional water saving system provided by the invention is reasonable in design and convenient to use, the water resource waste is avoided, and the use ratio of water resources is improved.