The fluid booster includes a main pipe and a auxiliary pipe. The main pipe is composed of a water inlet, a jet port, and a first-level pressurization chamber. The first-level pressurization chamber is tubular; the auxiliary pipe is connected to the main pipe. Outside the pipeline, they are connected to the first-level pressurizing warehouse of the main pipeline through holes; the auxiliary pipeline is composed of a second-level pressurizing warehouse and a third-level pressurizing warehouse. The fluid booster proposed in this utility model patent is connected to the fluid pipeline and provides fluid pressure through a three-stage booster chamber to supercharge the fluid to save the electric energy consumed by the water pump.