In this study, the effect of leadership style on organizational change management was explored in the case of Dashen Bank. Through an exhaustive literature review, the author learned that the leadership style is one of the leading factors in managing change in the organizations. However, there is controversy about the key leadership style for establishing change in the organization. This research project is aimed at finding out the effect of leadership styles on change management and the dominant predicting leadership style in the case bank, with a view to enhancing the practice of appropriate leadership and change management. The study used a descriptive and exploratory research design and used both convenience sampling and proportional stratified random sampling for interviews and questionnaires respectively. The target population of the study was 2084 and the sample size collected via questionnaires for further analysis was 252. The research also included the interview results of 6 senior managers of the bank. The qualitative data was analyzed using content analysis and the data obtained through the questionnaires was analyzed using SPSS version 21. The association between the independent variables (Transformational, Transactional, Authoritarian, and Laissez faire leadership styles) and dependent variable (Change management) was established using regression analysis, and descriptive statistics were utilized to substantiate it. The study's findings demonstrated that the bank used a variety of leadership styles to achieve its change objectives. The result of the regression showed that R2 =0.562, meaning 56.2% of the changes in dependent variables are explained by the independent variables. The study revealed that the transformational leadership style had a dominant positive and significant effect on change management followed by the transactional and Autocratic leadership styles. However, the study found out that Laissez-faire leadership had a positive and insignificant effect on change management. As the strength of the organization dwells much on the transformational style of leadership, the study recommended that the bank's management apply more of that and blend it with other leadership styles as needed in order to successfully manage change