Objectives The main aim of the article was to determine the impact of organizational culture on the effectiveness of managing cooperative banks. The research conducted by the authors focused mainly on the internal mechanisms functioning in these organizations, such as; leadership style, employee management style, analysis of factors ensuring organizational coherence, defining success criteria and factors motivating employees (often shareholders). Material and methods The methods used in the study included literature analysis and criticism, participant observation, comparisons, case studies, induction and deduction, synthesis. The main research tool was the OCAI (Organizational Culture Assessment Instrument) questionnaire by K.S. Cameron and E. Quinn, based on a competitive value model. The authors also defined the type of organizational culture according to T. E. Deal and A. Kennedy, based on the criteria of the degree of risk and the speed of feedback. 150 entities located in various regions of Poland were deliberately selected for the study. The research sample accounted for 28%. . The research was carried out in 2020 and 2021. Results The obtained results showed that cooperative banks are characterized by an autocratic management style. The autocratic management style does not correspond to the cooperative form. The type of culture indicated by the respondents requires modification consisting in the partial elimination of bureaucracy and autocratic personnel management, downgrading the features of the culture of gamblers and routines. Conclusions From a practical point of view, resolving the dilemma of whether profit is essential the purpose of a cooperative bank's operation has a key influence on the choice of a microeconomic model bank.