The invention discloses a leakage-free three-way pressure reducing valve which comprises a valve body. The valve body is provided with a port A, a port P and a port R. A swivel nut is arranged in thevalve body, a first valve base and a second valve base are arranged in the swivel nut, a first steel ball matched with the first valve port is arranged in the first valve base, a second steel ball matched with the second valve port is arranged in the second valve base, the first valve base is provided with a first through flow hole connected with the port P and a first valve port, the second valvebase is provided with a second through flow hole connected with the port R and a second valve port, the lower portion of the second valve base is provided with a push rod, the lower end of the push rod is matched with the first steel ball, the push rod is provided with a third through flow hole connected with the port A and the second valve port, a cylindrical pin is arranged in the swivel nut inthe radial direction, an ejector rod is fixed to the upper end of the second steel ball, and a large spring and a matched large spring base are arranged inside the swivel nut and located above the second valve base. The leakage-free three-way pressure reducing valve has the advantages of being simple and reasonable in structure, low in manufacturing cost and stable in operation.