Infrastructure such as water, electricity, and natural gas fundamentally underpins informal housing and industrial development in urban villages. Yet how the infrastructure is built, maintained, and governed, and what are the underlying mechanisms, remain peripheral to existing literature and policy agenda. This study addresses this gap by incorporating a socio-technical approach to infrastructure into informal urbanism to understand the negotiation of water, electricity, and natural gas in two neighboring urban villages in Chengdu, China. Four rounds of fieldwork and in-depth interviews with various stakeholders found highly precarious provision of infrastructure in urban villages. Its spatial layout, facilities, charges, quality control, and maintenance rest uneasily on, and then in turn shape, the development of informal renting markets and industries in different urban villages, especially when considering the cross-sectional interactions between different types of infrastructure. These processes are dominated by stakeholders’ commercial logics embedded in informal urbanism, including the urban village and infrastructure providers’ profit-seeking strategies, enterprises and migrants’ cost-saving behaviors, and the governments’ purposive absence in governing infrastructure, which leads to difficulties in meeting urban village residents’ needs for qualified infrastructure. This study unravels the “black box” of infrastructure in urban villages and puts forward inclusive planning strategies to promote infrastructure in urban villages.