Corporate governance is a relatively modern discipline. The trend of privatization initiated in the 1980s in many countries reinforced the importance of the private sector in the economy. The purpose of this thesis is to analyze the evolution of the Spanish regulation system on corporate governance, under the aspects of the history, culture, legal tradition of the country, and of the impact of European regulation, and the current financial crisis. The particular Spanish reality has led to a unique system of corporate governance, but with characteristics of various European corporate governance systems. The thesis defines corporate governance and the different systems of corporate governance coexisting in the European Union; secondly it makes a brief reference to the relation between the corporate governance system of Spain and the history, culture, and legal tradition of the country. Then, the research moves on to the current legal framework of corporate governance, focusing on the legal and regulatory aspects of corporate governance in the European Union and Spain. Next, the thesis deals with the weaknesses of the current regulation system of corporate governance that the crisis nowadays revealed; and then, it analyses the contents of both the European and the Spanish reform plans, included in the Action Plan of the European Commission published on 12th December 2012, and the Spanish Expert Committee on 14th October 2013, respectively. Finally, the thesis works on a conclusion of the corporate governance regulation system in Spain.