To investigate the impact of the inlet edge configuration on the performance of double-suction centrifugal pumps, this study focuses on analyzing the performance influence patterns under different flow angles within the same axial plane and across different axial planes. Specifically, the prototype pump"s inlet edge at the blade root and tip was swept forward by 10°, and subsequently repositioned circumferentially three times to establish 12 geometric configurations of the inlet edge under varying parameters. These configurations were subjected to internal flow field simulation analysis for different inlet edge forms. The simulation results indicate that the predicted external characteristics of the prototype pump are largely consistent with experimental data, confirming the effectiveness of the simulation method for internal flow field analysis. Among the geometric models, the three configurations with a 10°forward sweep at the blade root (Ba, Bb, Bc) exhibited optimal performance, with superior velocity distribution, pressure distribution, and cavitation resistance compared to the two models with circumferential repositioning and a 10° forward sweep at the blade tip. For double-suction centrifugal pumps, positioning the blade inlet edge on different axial planes and sweeping the blade tip forward can enhance pump efficiency, while sweeping the blade root forward improves cavitation resistance. Additionally, repositioning the blade inlet edge results in a more uniform total pressure distribution, reduces high-speed areas in the inlet region, and improves flow conditions. The study further confirms that there exists an optimal range for the parameter matching between the forward sweep at the blade root and the inlet edge position, and that a reasonable combination of settings can effectively suppress adverse flow patterns in the impeller inlet section.