The environment in the alpine and fragile ecological zone is sensitive and vulnerable, and improper disposal of domestic waste can easily aggravate the risk of ecosystem degradation. It is of great significance to reveal the multi-agent interaction mechanism and policy incentive effect of centralized domestic waste disposal among farmers and herdsmen in the zone for implementing domestic waste management, reducing ecological risk and improving living quality. Based on the case of the northern Xizang pastoral area, this paper, taking into account the realistic constraints of the alpine and fragile agricultural and pastoral areas, such as the cold climate, the scattered settlement of farmers and herdsmen, and the weak local fiscal strength, comprehensively considers the incentive measures of the village and town grassroots governments and the cost-benefit of farmers and herdsmen, and constructs a two-party evolutionary game model of the village and town grassroots governments and farmers and herdsmen participating in it, and examines the incentive effect of different policy measures and the interaction game mechanism of stakeholders through numerical simulation. The results show that: ①The participation of farmers and herdsmen is the key to improve the efficiency of centralized domestic waste disposal in the alpine and fragile ecological zone. The reward and punishment measures of the village and town grassroots governments can significantly motivate farmers and herdsmen to participate in centralized domestic waste disposal, and the constraint effect of punishment is more significant. ② The propaganda and facility construction measures of the village and town grassroots governments can significantly promote farmers and herdsmen to participate in centralized domestic waste disposal. The sensitivity of facility configuration to farmers and herdsmen's participation behavior is significantly higher than that of propaganda and education. Improving facility construction is the key measure to promote centralized domestic waste disposal. ③ In the future, it is necessary to optimize the centralized domestic waste disposal system for farmers and herdsmen in the alpine and fragile ecological zone, based on the cold climate, the scattered settlement of herdsmen and the pollution characteristics of the alpine and fragile ecological zone, optimize the planning, construction and operation management of centralized domestic waste disposal facilities, strengthen the inspection, evaluation and administrative management of village and town grassroots governments' participation in governance, and improve the incentive and constraint mechanism of farmers and herdsmen's participation in governance. This paper relatively systematically reveals the collaborative mechanism of centralized domestic waste disposal in villages and towns, which also has reference significance for the research and policy formulation of environmental governance problems in other regions.