The Panxi Plateau serves as a critical transitional zone from the eastern margin of the Qinghai-Tibet Plateau to the Sichuan Basin，forms a "plateau-plain" step-transition belt with the Chengdu Plain. Due to its dra‐ matic topographic relief and complex underlying surface properties，the plateau exhibits significant spatial het‐ erogeneity in soil resistivity. It has become one of the most lightning-active areas with the highest disaster risks in southwestern China. Lightning activity in this region is modulated not only by large-scale circulation systems （the South Asian Summer Monsoon，Plateau Monsoon）but also closely linked to meso- and microscale convec‐ tive processes induced by local topographic ascent and underlying surface inhomogeneities. Currently，research on the response regularities and driving mechanisms of lightning activity in this transition zone to key geographi‐ cal factors such as altitude and soil resistivity remains inadequate，with a particular lack of quantitative modeling and regional comparative analysis based on long-term observational data-thus failing to meet the targeted needs of lightning disaster protection under complex topographic conditions. This study，based on ADTD Lightning Lo‐ cation System data，digital elevation data，and soil resistivity data in Sichuan Province from 2010 to 2020， adopts spatial overlay analysis and quadratic polynomial regression methods，takes the typical geographical unit of the Panxi Plateau and the Chengdu Plain as the research object，and conducts research on the response regular‐ ities of lightning activity to key geographical parameters（altitude，soil resistivity，terrain-circulation synergistic effect）. The study results reveal that：（1）Cloud-to-ground（CG）lightning activity exhibits a distinct parabolic relationship with altitude（R²>0. 79），with distinct regional heterogeneities in its response characteristics. In the Chengdu Plain，CG lightning frequency shows a monotonic decreasing trend with increasing altitude，primarily due to high lower-atmospheric humidity that suppresses convective development-resulting in more active light ning activity in low-altitude regions. In the Panxi Plateau，by contrast，under the synergistic effect of topographi‐ cally forced ascent and local instability energy，a peak in CG lightning frequency occurs within the 1500-3000 m altitude range. This reflects the differential modulation of the unique thermodynamic and dynamic configuration of the plateau-basin transition zone on lightning occurrence processes.（2）Soil resistivity is a key factor govern‐ ing the spatial differentiation of CG lightning activity. In the Chengdu Plain，the proportion of CG lightning in the medium-resistivity zone（250-500 Ω·m）reaches 87. 9%，with a density of 2. 67 flashes·km-²·a-1；in the Pan‐ xi Plateau，the proportion of CG lightning in the high-resistivity zone（>500 Ω·m）is 94. 8%，with a density of 1. 57 flashes·km-²·a-1. This finding indicates that limited charge diffusion in high-resistivity regions facilitates the formation of strong electric fields，enhancing the probability of CG lightning occurrence and exhibiting a distinct charge accumulation threshold effect. Further analysis demonstrates an additional distinct positive correlation be‐ tween soil resistivity and CG lightning intensity-particularly in the Panxi Plateau，where the intensity of positive CG lightning is significantly enhanced under high-resistivity conditions.（3）The multi-factor coupling interac‐ tion of terrain-resistivity-circulation is distinct. The average density of total lightning in the Chengdu Plain is 1. 16 times higher than that in the Panxi Plateau，yet lightning intensity exhibits regional variations：the peak cur‐ rents of positive and negative CG lightning in the Panxi Plateau are higher，primarily driven by a synergistic mechanism involving strong charge accumulation（attributed to unique thermodynamic and dynamic conditions） and high resistivity that inhibits leader propagation（requiring greater breakdown energy）. This study not only ad‐ vances understanding of lightning formation mechanisms under complex terrain，but more importantly，provides a critical theoretical basis for lightning disaster risk zoning and lightning protection design in Southwest China.