Traditional villages in river basins preserve rural landscapes through both environmental adaptation and accumulated heritage governance. Taking 173 national-level traditional villages in the Fenhe River Basin as the study objects, this study examines their spatial patterns and the heterogeneity of influencing factors using kernel density estimation, nearest-neighbor analysis, spatial autocorrelation, optimal-parameters-based geographical detector, and multiscale geographically weighted regression. The villages display a significant clustered distribution rather than a random or administratively bounded pattern, forming a belt-like structure along the Fenhe River, its major tributaries, and mountain-basin transition zones, with high-density cores in the Taiyuan and Linfen basins. Among all examined factors, the enrichment of cultural relic protection units shows the strongest explanatory power in the OPGD results, with a q-value of 0.4349. Its MGWR coefficients are also predominantly positive and significant, suggesting that officially recognized heritage resources act as spatial anchors for the persistence and organization of traditional villages. Precipitation, elevation, intangible cultural heritage, per capita Gross Domestic Product (GDP), and historical post-road accessibility further shape village density, but their effects are spatially uneven. These findings suggest that conservation in the Fenhe River Basin should move beyond isolated village repair toward a watershed-scale linear heritage network linking river corridors, historical routes, cultural relic protection units, and cross-county governance.