The quest for understanding the relationship between the capital structure and investment decisions resulted in many different authors contribution. In the Brazilian economic scenario, an empirical study performed by Albuquerque and Matias (2013) identified the existence of a strong negative relation between finance leverage and investment in Brazilian public companies. The purpose of this study was to investigate whether the theory of finance supports these empirical findings or if there is a discrepancy between the practical behavior and the theoretical rules. To this end, it was performed a bibliographic research of scientific works related with this theme, among them Carneiro, Salles and Wu (2006), Hadlock and Pierce (2010) and Dang (2011). The methodology of this research can be classified as exploratory, according to its purpose, qualitative in terms of approach and bibliographical considering its technical procedures. All the developed analysis led to the formulation of six theoretical propositions that support the relation between financial leverage and investment. The negative and positive effects of debt were considered according to growth opportunities, the supply of credit in the Brazilian context, the raising of risk and cost of capital and the allocation of resources obtained through external funding. Briefly, it can be concluded that these six theoretical propositions could serve as the fundamentals of the relation in question, two being based on the under-investment and overinvestment theories and the other four, on the Brazilian financial market aspects. All of them must be considered in the decision making of a financial manager, especially the related with the financing options