Scientists worldwide are exploring strategies to mitigate the increasing frequency of extreme climate events, such as heatwaves. Urban areas and their altered microclimates have been extensively studied globally, often through case-specific research examining how urban geometry impacts microclimates and outdoor thermal comfort. This paper aims to review the global research done on Urban Heat Island (UHI) in the context of urban geometry because such reviews were scarce. It presents a systematic review of global literature, explores theories and concepts like urban heat islands, and discusses how these findings can address challenges in Indian urban contexts. The methodological approach in this paper analysed the paper under four aspects: urban environmental parameters, urban climate zones, the timeline of studies, and data collection. It further highlighted the fact that there is a notable lack of research on urban geometry and microclimate in India—a rapidly urbanising nation with a growing number of megacities. The present review provides insights relevant to Indian composite climate cities and the need for more research, especially in the area of urban geometry, thermal characteristics of construction material, and field monitoring. By identifying key research priorities, the review outlines a framework for integrating microclimate considerations into sustainable urban design in India. It aims to guide future interdisciplinary research and inform policy interventions for heat stress mitigation.