BACKGROUND AND OBJECTIVES: The objective of this systematic review was to determine the outdoor environmental factors that are associated with increased risk of falls and fear of falling in middle-aged and older adults. RESEARCH DESIGN AND METHODS: PubMed, Medline, EMBASE, APA Psych INFO, and CINAHL electronic databases were searched through August 2024 for studies that included participants 45 years or older, falls or fear of falling as an outcome, and measure the outdoor environment (i.e., uneven sidewalks, neighborhood disorder). Title and abstract screenings, full text screenings, and critical appraisal assessments were independently reviewed. RESULTS: The search retrieved 7474 records, 627 full texts were reviewed, and 51 unique studies met the inclusion/exclusion criteria. The number of participants ranged from 12 to 6,720,937. There were 41 studies that included fall outcomes, 5 studies that included fear of falling outcomes, and 5 studies that included both outcomes. Micro-walkability (e.g., sidewalk quality) were the most frequently studied outdoor environmental characteristics and many studies found associations with falls and fear of falling. Macro-walkability (e.g., land use), crime and safety, socioeconomic, greenspace, terrain, physical disorder, and social features were studied to a lesser extent and had mixed findings. DISCUSSION AND IMPLICATIONS: The most consistent associations were found between micro-walkability features of the outdoor environment with falls whereas other environmental domains and fear of falling were studied to a lesser extent. Environmental contributors to falls should be considered in future research, policy implementation, and clinical interventions to reduce falls and their negative outcomes for older adults.