Abstract: Drawing upon holistic governance, collaborative governance, and symbiosis theory, this paper constructs a four-dimensional integrated analytical framework of ‘institution-technology-actor-symbiosis'. Using a multi-case comparative approach, it systematically examines the safety supervision practices for small and scattered construction projects in Xiamen, Dongguan, and Shenzhen across three dimensions: institutional variables, technological pathways, and actor collaboration mechanisms. Optimization strategies are proposed, including establishing a registration and management system that covers both urban and rural areas, introducing risk reduction services in a differentiated manner, building a unified digital platform, and expanding grassroots symbiotic networks. The findings reveal that the governance of small and scattered construction projects follows a progressive logic of ‘fragmented integration-multi-actor collaboration-ecological symbiosis', with mutualistic symbiosis serving as the key mechanism for sustainable development. The adaptive regulatory paradigm that integrates ‘rule of law, technology, and co-governance' demonstrates transferable value across urban and rural contexts, and its extension to rural areas must be organically integrated with planning control, land use management, and village self-governance institutions.