The invention relates to a high-pressure double suction pump. The pump comprises a suction chamber, a pump case, an impeller, a shaft, a packaged mechanical seal device arranged between the pump case and the shaft, an impeller ring seal device and a mechanical seal flushing device, wherein the suction chamber comprises a suction port, a flow distributing section and a spiral section; the flow splitting section comprises a left passage, a right passage and a volute wall between the left passage and the right passage; the volute wall is provided with a water distributing tongue extending towards the suction port; and the outer surface of the flow distributing section of the suction chamber is provided with at least one radial reinforcing rib which encircles the flow distributing section by a circle. The double suction pump solves the technical problems of low efficiency of the suction chamber, long time of hydraulic strength tests, easily failed mechanically sealed brake device and poor sealing effect of the ring, improves the efficiency of the suction chamber, shortens the testing time, reduces tooling, and stops the problems that the brake device flicks and fails in a high pressure working environment.