Abstract: Today, due to an intense competition in service sectors, the role of customers’ loyalty has been more prominent than before. In recent perspective, marketing includes growth and satisfaction and according to the customer’s opinions quality is loyalty and effective communication with the customers. The purpose of this study was to investigate the quality of the relationship with the customer on customer’s satisfaction and loyalty (a case study of customers of Tejarat bank in Zahedan City). According to what was said, the present study is a practical research and the method of study is descriptive. Besides, this is a field study because data collection was done by using questionnaire in order to obtain the customers’ opinions. This is a cross-sectional study since it was done in a certain time interval. The statistical population included all customers who referred to Tejarat bank in Zahedan. A simple random sampling method was done and because of unlimited number of customers, 383 questionnaires were distributed randomly among Tejarat bank customers. In order to collect the data regarding the general issues and theoretical framework, library studies and field studies (questionnaire) were used while its validity was confirmed by some university professors and its reliability was measured by using Cronbach alpha (higher than 0.7). Data analysis was done through descriptive statistics such as frequency tables and diagrams and in order to describe the data and hypotheses inferential statistical methods including correlation coefficient, linear regression and modeling were used. The results showed that the quality of the relationship with the customers affects the customers’ satisfaction and loyalty and satisfaction also has an effect on their loyalty. It is recommended that they increase marketing tactics based on raising the customers’ awareness of the brand such as running programs of social responsibility.