This research seeks to study the influence of Corporate Social Responsibility (CSR) on the reputation of a corporation from a strategic point of view. The literature review suggests the absence of this type of study for the banking sector in emerging countries. In this sense, this research seeks to contribute to a better understanding of the CSR effects on the corporate reputation (CR) in the banking sector in Peru. By using the methodology of the case study, the four most relevant banks in Peru have been analyzed representing 25% of all participants of the banking system in Peru and 80% in the participation of three financial indicators: % credits, % deposits and % patrimony (equity) and, it has been detected that CSR could affect both corporate reputation (CR) and the investor's confidence. In addition to this, it has been found that CR could act as a moderating variable between CSR and the investor's confidence. Peruvian banking companies have improved their reputation due to their social responsibility actions. This improvement of reputation has been correlated with a strengthening of enterprise value. Likewise, the analysis of each of the cases, within the scope of the plans of CSR, seven propositions were detached classified in three relations (CSR and investor confidence, CSR and corporate reputation, and corporate reputation and investor confidence). The novelty of this work is twofold. The literature has analyzed the concepts of CSR and CR in an isolated manner. After a thorough review a model that relates the two concepts is proposed. Secondly, the model is used to pose hypotheses of the relation CSR and CR in financial sector companies in developing countries. Research in this topic has been done mostly in production enterprises and in developed countries.