Urban ecosystems differ from non-urban ones in the strong and rapid biocultural dynamics generated by the interactions between people from different cultures, at large spatial and temporal scales, and very fast rates. This opinion piece explores the concept of urban ethnobiology as a critical field of research that investigates the complex and dynamic biocultural systems that exist in urban environments. We argue that interactions between humans and other life forms in urban ecosystems are influenced by a characteristic set of social, cultural, and political factors that are linked to urban environments, such as infrastructure development, population density, and governance structures. We emphasize the need for an interdisciplinary approach that brings together experts from different fields to study the inherent complexity of these systems. By examining the sociocultural dynamics that shape the way urban biodiversity is perceived, used, and managed, we can gain deeper insights into the different dimensions of socio-cultural biodiversity in urban areas.