A household car wash water gun is a device that generates high-pressure water flow by connecting to a household water source (such as a faucet) and using an internal structure (such as a high-pressure plunger pump) to increase water pressure. It usually includes components such as a water gun body, an adjustable nozzle, a connecting water pipe and an adapter. The user holds the water gun, controls the nozzle to adjust the water flow shape and pressure, sprays high-pressure water directly onto the vehicle surface, and uses the impact force of water to remove dirt.