This thesis examines determinants of banks’ profitability in the European banking sector. The descriptive analysis indicates that the banking sector is unique compared to other industry sectors since the sector is heavily regulated and since that commercial, mutual, co-operative and government-owned banks jointly operate in the sector. Hence, the empirical part of this thesis takes into account, in particular, regulation and ownership issues. The analysis extends research of Dietrich and Wanzenried (2011) by examining additional determinants of banks’ profitability and by focusing on the European banking sector. Apart from examining the determinants of banks’ profitability, potential impacts of the financial crisis are considered. Using an unbalanced panel of 354 banks between 2000 and 2009, this thesis shows that profit persistence still exists in the banking sector. Besides, findings suggest that the equity-to-asset ratio is positively related to banks’ profitability supporting the bankruptcy cost hypothesis or signaling hypothesis. There is no evidence found that the funding- and liquidity structure are determinants for profitability, both proxies appears to be insignificant. Besides, little evidence is found for the agency theory.