Abstract: In the context of China's transition toward high-quality urban development, community streets-as vital carriers of urban spatial vitality-have become key entry points for the renewal and quality improvement of builtup areas. This study investigates community street vitality from the perspective of walking and lingering behaviors, based on in-situ observations within a community context. First, classical spatial design theories related to street vitality are reviewed, and a multi-scale indicator framework is established that incorporates both meso- and micro-scale built environment variables. Then, using behavioral observation data from typical street segments, the study analyzes the spatial correlation mechanisms between built environment features and street vitality. The findings reveal that: 1) Street vitality varies significantly by behavior type, walking and lingering should jointly represent vitality, as a single metric such as pedestrian volume cannot fully capture spatial vitality; 2) At the meso scale, functional mix and road connectivity are strongly associated with walking vitality; 3) At the micro scale, the density of street furniture significantly influences lingering behaviors. Different types of lingering show varied sensitivities to environmental elements: commercial lingering is largely affected by street interfaces; recreational and cultural lingering rely on adequate facilities and appropriate spatial scales; while social lingering is less influenced by the physical environment. These findings provide theoretical support and design guidance for vitality-oriented renewal and fine-grained improvement of existing urban streets.