The built-environment morphology of traditional settlements is a spatial outcome shaped by mountain–water patterns, architectural fabric, street–alley networks, and long-term human adaptation. To reveal the morphological differentiation and typological spectrum of Dong traditional settlements in southwestern Hunan, this study examined 33 settlements and developed a multi-scale identification framework integrating the terrain-constraint scale and the morphological-structure scale. Using unified boundary delineation, indicator extraction, standardization, hierarchical clustering, cross-tabulation analysis, and association tests, three terrain-constraint types were identified: the high-elevation dissected and water-distant type, the footslope transitional and water-adjacent type, and the low-valley and water-attached type. Three morphological-structure types were further identified: the compact-clustered type, the elongated-loose type, and the aggregation-enhanced type. The results show a significant and moderate-to-strong association between the two type systems. Based on the dominant T–M combinations, three integrated typological types were synthesized: the high-elevation dissected–compact-clustered type, the footslope transitional–elongated composite type, and the low-valley–aggregation-enhanced type. The findings not only provide a basis for typological identification and morphological comparison of traditional Dong settlements but also support the selection of representative settlement types for subsequent microclimate analyses. By distinguishing the characteristics and management priorities of different settlement types, the proposed framework provides a scientific basis for differentiated conservation planning, landscape management, and climate-adaptive renewal of traditional Dong settlements.