Street trees are components of the urban forest that receive considerable attention across academic and professional disciplines. They are also one of the most common types of urban tree that people routinely encounter. A systematic review methodology was used to examine contemporary urban street tree research across natural and social science disciplines. The records collected (n = 429) were published between January 1997 and the mid-2020s and were coded for descriptive information (e.g., publishing journal and geography of study areas) as well as emergent focal research areas (e.g., ecosystem services, economic valuation, and inventory methods). From this sample, there has been considerable growth in street tree literature over time and across research themes, especially following major turning points in the field of urban forestry. Regulating ecosystem functions/services of street trees, especially cooling, has had the greatest attention in the literature, but other robust areas of research also exist, including the utility of pruning waste as construction materials, the benefits and disservices to human health and safety, and indicators of environmental (in)justice. Opportunities for future research and implications for research and practice are also discussed.