Background: The purpose of this study was to investigate the relationship between a Think Tank and decision-making styles of the managers of Refah Karegaran Bank. Reform and improvement of the decision-making style in the area of banking system which are the need to provide electronic services in the information age. In the 1404 vision of Iran, managers decision-making improvement has also been seen as an important scenario. Therefore, managers' decisions in this area are related with economic, social, and political factors, and those are highly ambiguous and complex. The relationship between independent and dependent variables was investigated based on Scott and Bruce's 5-dimensional model. Objective: Therefore, with this increasing changes, managers and heads of banks can not alone keep up with these complexity. Hence, it requires the elite and expert in this field to remain in the competition and to achieve the most important issue in today's banking, namely Customer orientation. In this regard, the purpose of this article is to survey the relationship between the think tank and decisions of managers in the Refah Bank. Method: This research was descriptive-survey. The statistical population of this study was 67, but the researcher selected only 30 managers by simple random sampling. The data collection tool was a researcher-made questionnaire and a standarded questionnaire based on Scott and Bruce's decision making styles, whose validity was confirmed by the professor and experts and its reliability by Cronbach's alpha was in pre –test samples 0.897. Findings: Data was analyzed by SPSS software. Kolmogorov-Smirnov test was used for data normalization and Pearson correlation coefficient was used to determine the relationship between variables. Conclusion: Data analysis indicated that there is a meaningful relationship between the think tank and decision maker styles. The instant decision making style had the highest correlation of 0.798 with the Think Tank, and then the intuitive style with a coefficient of 0.739, and the minimum relationship was the model of the Trash Can Model with the think tank in Refah Karegaran.