Against the backdrop of ongoing rural population decline and the weakening of community subjectivity, tourism-based villages face a pressing challenge: how to reconstruct sustainable local support systems.Traditional approaches to community development often rely on the long-term participation of permanent residents; however, in depopulated and aging regions, such models are increasingly unsustainable. In response, this study takes the Yuki-tōrō Supporter Program in Kayabuki-no-Sato, Miyama Town, Kyoto Prefecture, Japan, as a case study. Grounded in subjectivity theory and based on qualitative methods including participant observation and semi-structured interviews, the research focuses on tourists as "mobile subjects" and explores how their short-term involvement in tourism-based community development can contribute to the regeneration of village subject structures. Findings reveal that tourists demonstrate distinct characteristics of subjectivity through their participation: 1) self-driven motivation and active practice rooted in personal interest, cultural identification, and value pursuit; 2) dynamic role negotiation between being service providers and experience seekers; and 3) the accumulation of subjective experience through repeated participation and cross-regional mobility. Based on these insights, the study proposes a threefold mechanism for village subject regeneration: first, the institutional empowerment of tourists through the creation of short-term participation platforms to activate and convert their subjectivity into localized support resources; second, the dynamic balancing of service obligations and individual experience needs through flexible role coordination; and third, the spatial and temporal extension of tourist subjectivity as a foundation for building regenerative support networks across regions.