The subject of this paper is a study of the influence of organisational culture on business performance of enterprise BH Pošta Sarajevo, one of the largest enterprises in Bosnia and Herzegovina. In the first part of the article, basic information on organisational culture, business performance and their relationship necessary for understanding of the empirical part of the paper are given. The latter part starts by analysing the question whether a strong organisational culture exists in BH Pošta. The research attempts to reveal which type of organisational culture is present within the enterprise, and whether the culture influences successful business performance. Therefore, the purpose of the paper is to make an objective assessment of present organisational culture and its impact on the business performance, theoretically and in the case of BH Pošta.