This study aimed to investigate the impact of six different metrics of the built environment on walkability and mental health in New York City (NYC) and identify which metrics have the most significant influence. The study utilized data from NYC Open Data, the American Community Survey, and 911 calls and employed various statistical methods such as multiple linear regression and clustering analysis. The results revealed that the presence of trees, street lights, and restaurants have a positive impact on walkability and mental health, while smoke shops and liquor shops have a negative impact. Building height has a mixed effect, depending on the neighborhood. The analysis of 911 calls data provided further evidence of the impact of the built environment on mental health. Specifically, areas with lower walkability scores had a higher number of mental health-related emergency calls. Overall, the study provides insights into how specific metrics of the built environment can impact mental health and walkability in urban settings.