The thickness of the S50-160/75 standard pump volute calculated by the traditional formula was amended to solve the volute wall of the domestic standard pump. The pressure distributions in the volute along the flowing were simulated by using Fluent software, and the trends were from rising to declining to rising again in low flux condition and rising gradually in rated condition. The stresses and strains have been calculated approximately in different conditions with ANSYS software, it concluded that the throat section and the largest ring of the axial region are the most easily damaged and the most dangerous parts. Strength check on the volute and finite element analysis showed that the amended thickness of the volute met the strength requirements. And the hydraulic performance tests of the pump proved that the calculated results are consistent with the actual results.