Abstarct: The environment of the neighborhood and its public spaces have a significant effect on the social interactions and psychological well-being of the people living there. Neighborhood parks, as one of the main public spaces in every neighborhood, can help improve the well-being of residents by providing suitable facilities and opportunities for social interactions. These spaces can act as places to gather, talk and create new connections. But at the same time, if the design of these parks is not done properly, it may have the opposite result. In such a situation, the residents may give up using these spaces, and as a result, social interactions between them will decrease and, in this way, have negative effects on their quality of life. Therefore, paying attention to the correct design of the park is of particular importance so that they can act as a positive and productive space for the society. Therefore, the main goal of this research is to determine the effect of neighborhood environment on social interactions and well-being of its residents. The approach of this current research is an applied and cross-sectional research according to the research problem. The research strategy is quantitative and in the context of correlational research. In this research, the investigated statistical population is made up of the residents of the investigated neighborhoods of Shahrood city baxsed on the master plan of Shahrood in 2019. In the current research, 2 neighborhoods in Shahrood city will be selected as case samples baxsed on the environmental characteristics of their neighborhoods, which were randomly evaluated. Daniel Soper's method was used to determine the sample size of this research and 264 questionnaires were determined baxsed on the research variables. Descxriptive statistical methods and inferential statistical methods including exploratory factor analysis and full structural equation modeling were used for data analysis. The software used in this research was SPSS26 and PLS4. The results of the research showed that readability, diversity, attractiveness, and comfort variables had a positive effect on social interactions, but the environmental factors examined in this research had no effect on psychological well-being. At the end, according to the obtained results, solutions for improving the neighborhoods were stated.