The invention relates to the field of fluid machines, and provides a multistage centrifugal pump delivery chamber which is small in axial size and easy to cast and assemble. The multistage centrifugal pump delivery chamber comprises a first annular runner, a diffusing section and a second annular runner located on the outer side of the first annular runner. The second annular runner is formed in the inner side of a shell and located at an outlet of a first final-stage guide vane. The areas of all sections of the second annular runner are equal. The first annular runner is formed by matching a rear cover plate of the first final-stage guide vane and a rear cover plate of a second final-stage guide vane. The diffusing section is in a horn shape, is located on one side of the second annular runner, and communicates with the second annular runner.