To investigate the influence of cloud microphysical processes on a heavy rainfall event in the northeastern Sichuan Basin,sensitivity experiments using different microphysics schemes were conducted with the WRF (weather research and forecasting) model version 4.3,driven by FNL global reanalysis data. The simulations focused on a typical rainstorm that occurred from October 4 to 5,2022,and were evaluated against CMPAS (China Meteorological Administration multi-source merged precipitation analysis system) precipitation data and GPM (global precipitation measurement) satellite products. Results indicated that all six microphysics schemes reproduced the general northeast-southwest-oriented distribution of rainfall,although simulated intensities were generally weaker than observed. Among the schemes,Lin and WSM6 produced precipitation centers and spatial patterns most consistent with observations. In terms of cloud structure,simulations using Lin,WSM6,and WDM6 schemes aligned best with cloud distributions captured by GPM. The vertical distributions of cloud water,rainwater,and ice water varied significantly among schemes,contributing to differences in simulated rainfall. Compared with GPM data,the WSM6 and WDM6 schemes demonstrated better vertical correspondence of hydrometeors across different time periods and altitudes. Variations in the formation and growth of snow and graupel also played a critical role in simulation discrepancies,reflecting differences in microphysical structures and the distribution of hydrometeors. The Lin scheme produced the most graupel and the least snow,which may have limited ice-phase precipitation enhancement. In contrast,the CAM scheme lacked graupel,hindering the formation of heavy rainfall,while the Thompson and Morrison schemes simulated only small amounts. The WDM6 scheme showed a precipitation peak near the 0 ℃ layer in the upper warm layer,with a downward decrease in intensity,suggesting weak collision-coalescence processes and significant rainwater evaporation. Overall,the WSM6 scheme produced the most accurate simulation,yielding a more realistic spatial distribution of hydrometeors and closer agreement with observed extreme precipitation.