摘要：An important decision that any company should take is to think how it is financed, whether their resources will be their own or from third parties. There are two schools of thought, the Classical Theory (1952) and Modigliani and Miller (1958). The classical theory is in the idea hat the market value of the company is influenced by how the entity financed its resources, going against the current theory of Modigliani and Miller proposed that in an ideal world the way the company capital structure no influence on its market value. Through this contradiction, the article aims to discuss the relationship between sources of financing, results and their impact on market value in 1000 (thousand) best companies in Brazil, listed in magazine exame, july edition of 2010. This analysis was performed using multiple regression, which listed the traditional indices of profitability and rates of capital structure with the market value of the companies analyzed. As a result, there was a correlation between the dependent variables and their effected only when the sector by regression analysis. In analyzes that considered all cases of the population the hypotheses were not confirmed.
