Urban heat islands (UHIs) have been investigated from various perspectives. However, little is known about UHImitigation strategies in terms of UHI networks and the overall connectivity. Therefore, we developed a research framework to construct a UHI network from a connectivity perspective in a typical "furnace city"-Fuzhou city, China. Initially, morphological spatial patterns, mean standard deviations, and landscape connectivity were analyzed to identify UHI sources and assess their importance. Subsequently, six natural and socioeconomic factors were integrated into the model to create a combined resistance surface for thermal diffusion. Finally, circuit theory was applied to build a UHI network and pinpoint key nodes. Our results show that the combined resistance increased from the center of the study area to the periphery. In addition, 38 UHI sources, 84 thermal corridors, 30 heating nodes, and 21 cooling nodes were identified. The UHI sources and key nodes were primarily distributed in an uneven manner in the nuclear and northwestern regions of the research area. Furthermore, cooling measures were developed for UHI networks to reduce network connectivity. Our research framework offers a new perspective for promoting healthy urban development and climate-adaptation planning.