Urbanization and climate change are exerting significant pressure on the living environments of traditional rural settlements. In western Sichuan, the persistently cold and humid winter further intensifies the risks for local residents. Linpan, a distinctive agricultural settlement form that has evolved over centuries, embodies climate-responsive construction wisdom shaped by long-term human–environment interaction. Within Linpan, residential units—composed of outdoor and indoor spaces—serve as the primary activity spaces for inhabitants. Their spatial configuration and construction practices directly regulate the thermal environment and consequently influence daily life. However, whether the winter thermal environment satisfies contemporary thermal comfort requirements, and which landscape and construction determinants can effectively enhance thermal adaptation, remains insufficiently understood. To address this gap, this study integrated meteorological field measurements, thermal comfort questionnaire surveys, and coupled numerical simulations to systematically investigate winter thermal conditions in both outdoor and indoor spaces of Linpan residential units. The optimization performance of key landscape determinants (vegetation configurations and ground materials) and construction determinants (building layouts and envelope materials) was evaluated. The results reveal climate-responsive passive design strategies based on actual inhabitants’ thermal adaptation, establishing a sustainable design framework for improving winter thermal comfort in traditional agricultural settlements. The findings provide scientific support for rural revitalization and contribute theoretical insights into climate-resilient preservation of vernacular dwellings under changing environmental conditions.