Urban ecology research plays a crucial role in understanding the intricate relationships between urban landscapes and their ecological effects. A fundamental requirement for this type of research is the establishment of clear and consistent urban boundaries. Previous studies commonly used remote sensing images to map these urban boundaries. Due to the varying pixel sizes of different types of images, significant discrepancies arise in how urban boundaries are delineated. This lack of a standardized mapping unit poses substantial challenges, as it diminishes the comparability of urban boundaries derived from different pixel sizes. Consequently, this inconsistency can affect analyses and comparative studies of urban ecological environments, undermining the robustness of findings in urban ecology. In response to these challenges, we propose a novel method for extracting built-up areas based on urban road networks. This innovative approach aims to enhance the comparability and accuracy of urban boundaries by establishing a unified mapping unit. The methodology begins with the segmentation of road networks using high-resolution imagery. This segmentation is then complemented by integrating information from multiple remote sensing data sources, which enables more precise identification of urban built-up areas. The outcomes of this research indicate that the new method substantially improves extraction results by addressing common issues associated with built-up area delineation, such as fragmentation, jagged edges, and irregular shapes. These improvements are critical as they enhance the visual and analytical clarity of urban boundaries, making them easier for researchers and urban planners to use. Moreover, by standardizing the mapping units, the method effectively mitigates non-comparability issues that often arise from using diverse pixel sizes. Importantly, the overall accuracy of built-up area extraction is found to increase by 2% to 4% compared to traditional methods.The road network-based extraction technique not only refines the process of delineating urban boundaries but also strengthens the foundations of urban ecology research. With more accurately defined urban boundaries, researchers can conduct analyses that yield valuable insights into the interactions between urbanization and ecological processes. This has profound implications for urban planning, as it allows for better-informed decision-making and resource allocation. In summary, the proposed method represents a significant advancement in urban ecology research, promoting greater consistency, accuracy, and comparability in urban boundary delineation. This innovation not only enhances our understanding of urban ecological patterns, processes, functions, and services but also supports sustainable urban management practices, ultimately contributing to the resilience and sustainability of cities in an era of rapid urbanization.