This study aims to investigate the needs of children and their caregivers in cities and whether their needs can be quantified through objectively methods and improved according to the suggestions that is based on the indicators of their needs. In this research, we adopted a data-driven approach to urban morphology by collecting urban structure data on Open Street Map of four major cities and analyzed the traffic ways and service facilities according to the needs of children and their caregivers, for defining the "maternal and child friendly indicators” for cities. This study outlines the process of collecting and analyzing open data from urban geographical sources and quantifying "friendliness" as a case study in data-driven urban design. With the urban morphology approach, we analyzed the road composition by calculating the segmentation points and street lengths, as well as the distribution of maternal and child-friendly service facilities. After determining the indicators of maternal and child friendliness, we applied them to five cities in Taiwan to confirm their accuracy and provide improvement suggestions for more maternal and child-friendly environments.