The invention provides a self-supporting nanofiltration machine and relates to a novel nanofiltration machine (NF) and a water purifior (RO), and is suitable for preparing general municipal direct supply tap water (hydraulic pressure >=0.2 MPa) or pure water in region without direct supply water source. The self-supporting nanofiltration machine comprises a solenoid valve 1, a supercharging water pump, a pre-processor, a solenoid valve, a nanofiltration apparatus, a pure water storage tank with liquid level signal, a control panel, a solenoid valve 3 and a concentrated water solenoid valve; a solenoid valve 1 water inlet is connected to a water supply line by an inlet pipe, and a solenoid valve 1 water outlet is connected with the supercharging water pump water inlet by a pipeline, and the supercharging water pump water outlet is connected with a pre-processor water inlet by pipeline, and one end of the pre-processor water outlet is connected with a nanofiltration apparatus water inlet by pipeline, and the other end of the pre-processor water outlet is connected with a solenoid valve 1 by pipeline; the nanofiltration apparatus is provided with a pure water outlet and a concentrated water outlet, and the pure water outlet of the nanofiltration apparatus is connected with the pure water storage tank.