This paper aims to analyze the effect of perception of nature in the built environment on the sociability of spaces. In this paper, quality of sociability of spaces is considered as a dependent variable which can be affected by possibility and quality of perception of nature in the built environment as independent variables. In order to make the analysis, built environment is considered as a socio-behavioral setting which makes a socio-spatial system. The process of research includes a specific approach to make a basic framework based on the literature of environmental psychology while exploring main components of interactions between natural environment and built environment. Then the research explores various aspects of quality of sociability in the built environment based on perception of nature. The main hypothesis is that there exists a correlation between perception of nature and sociability of the built environment. This work utilizes a multiple case study research methodology to understand the effects of perceiving and experiencing nature in the built environment on quality of sociability of spaces. In fact based on fundamental theories of environmental psychology main considerations are made on study of lived spaces and case studies are selected from residential buildings in Hamedan. Thus based on theoretical framework the main strategy is a qualitative method to access the correlation between two main variables by applying various tactics which are including interviews, questionnaires and direct-depth observations. The data were collected by means of a survey conducted on case studies and filling out the survey was done individually at the participant's homes. Correlation between place attachment and experience of nature were investigated through considering related indicators by applying two main stages. In first stage, the level of place attachment was measured by means of direct interviews and considering critical items. In the second stage, nature perception and how to experience it, were measured by means of the criteria which are derived based on literature review. Measures focused on participants’ respective their life spaces and management of these areas. At last two sets of data were collected from participants of 27 case studies to shape next steps of evaluation. The case studies were selected from three main types of residential spaces in the city of Hamedan which are including urban houses, House-gardens and Apartments. As the basic variables of research were qualitative, based on a hierarchical process, each variable were considered in sub-items. Each sub-item was measured in turn, by nominal quantities using a 5-point Likert-type. Based on analyzing Pearson Correlation, quantitative analysis verifies the assumed correlation between major variables of research-sociability of spaces and perception of nature-based on hypothesis. As expected, based on literature review, calculation of correlation shows the existence of a significant positive correlation between the sociability of spaces and nature perception. The score of correlation is meaningful and important.