Abstarct: Identifying the level of vitality through significant indicators is a crucial analysis to assess a space's functionality. Due to rapid urbanization and urban development, the decline in the environmental quality of neighborhoods and the spaces where citizens can interact has led to a decrease in neighborhood vitality. Given the lack of research on the impact of the physical environment and social interactions as a mediator on vitality, this research becomes necessary. Furthermore,previous studies on vitality have not considered this variable independently of physical environmental factors. Therefore,this study aims to examine vitality indicators separately from the physical environment. ‫This research aims to evaluate and enhance the level of vitality in urban neighborhoods by examining the factors affecting this phenomenon in Imamieh and Rahnamaie neighborhoods of Mashhad. The statistical population of this research consists of the residents of these two neighborhoods. The sample size includes 400 residents in both neighborhoods (200 in each neighborhood), collected through a quota sampling method baxsed on age and gender groups. Data was collected using a questionnaire; the initial validity of the questionnaire was confirmed by a group of university professors, and the initial reliability with Cronbach's alpha coefficient of 0.744 was considered acceptable.‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬‬ Data analysis methods were conducted using exploratory factor analysis in SPSS version 26 and structural equation modeling in Smart PLS version 4. According to the findings, the factors extracted from the physical environment that affect vitality in order of impact are: access and mixed-use, satisfaction with shopping conditions, and environmental stressors. Social interactions were identified as a mediator between independent variables and the dependent variable of vitality. As a result, strategies have been proposed to improve the physical and social environment to increase vitality.