Knowing the customers of shopping centers contributes greatly to increase profits of these centers. Customers’ segmentation is one of the most effective means of knowing customers. The purpose of this study was to present a segmentation of customers based on their activities in the shopping centers. The participants were 157 visitors of Milad-e-Noor Shopping Center who were required to answer the questions in the questionnaire. Data were analyzed in three steps. Through the use of factor analysis, in the first step, the number of variables was reduced to the four factors of entertainment activities, planned shopping, shopping information gathering, and unplanned shopping. These factors were then inserted into K-mean cluster analysis and, in the second step the visitors were divided into 4 segments on the basis of their activities as following: traditionalists, shopping center enthusiasts, wandering customers, and entertainment seekers. In the third step, the demographic and behavioral variables were investigated in the identified clusters. Considering the variables of age, academic status, and accompanying persons in shopping centers, these clusters were significantly different. However, in respect to the variables of sex, marital status, the length of presence in the shopping centers, occupations, and monthly salary they were recognized as homogenous.