Abstarct: According to research conducted in developed countries, the design of neighborhood units affects physical activity, lifestyle, health and human well-being.However, there are a limited number of studies in the Middle East that have examined the types of design of neighborhood units and urban form and its relationship with physical activity and health and well-being. Due to the lack of information in this field in the city of Mashhad, in this study tries to investigate the relationship between walkability, physical activity, health and well-being of adults in the city of Mashhad as one of the major cities in Iran and the Middle East. Thus, in this study, three types of of neighborhood design in three areas of Mashhad with different characteristics have been selected and the amount of walking and its effects on physical activity, well-being and health have been studied. To investigate the relationship between the characteristics of the walkable neighborhood, physical activity, health and well-being, a survey was conducted in three areas of Mashhad. The research questions are as follows: 1. Is there a significant difference in the level of adult well-being and different urban forms in large cities of Iran? 2. Is there a significant difference in the level of physical activity and health of adults and different urban forms in large cities of Iran? 3. To what extent do the variables of personal, socio-economic relationship, city shape, lifestyle correlate with adult well-being? In this research, descxriptive statistical methods including mean and standard deviation and frequency of demographic variables have been used. All qualitative data obtained from the questionnaires have been converted into numerical data through SPSS. According to the present research, it can be concluded that the more appropriate the urban structure, the higher the well-being rate. Also, with increasing the quality of the urban structure, the amount of physical activity and health also increases, and vice versa, reducing the appropriate urban structure can reduce the amount of physical activity and health. It can be concluded that using more quality in lifestyle, leads to a significant increase in the rate of well-being, and vice versa, by reducing the quality of lifestyle, the amount of well-being decreases.