This study aims to identify the factors that influence the level of disclosure of information about operating segments of Brazilian companies. The study is initially developed from the analysis of companies’ financial statements with reference to the requirements contained in Pronouncement CPC 22. Subsequently, the statistical model of multiple linear regression analysis is used. The disclosures related to 2010 and 2011 are addressed; 2010 was the first year that the disclosure was mandatory in Brazil. The study encompasses 272 companies distributed across 20 economic sectors. Hypotheses concerning 8 characteristics identified as potential factors affecting the level of disclosure, based on the theory and previous studies on the subject, are tested. No significant results were found for the characteristics “profitability”, “industry concentration”, “profit or loss” and “year of publication”, indicating that these factors do not influence such disclosure. Overall, the results show that with respect to the level of disclosure about segments, (i) the larger the company, the higher the level of disclosure; (ii) the greater the degree of company indebtedness, the higher the level of disclosure; (iii) companies listed in the BM&FBOVESPA’s Levels of Corporate Governance exhibit higher disclosure levels than the others; and (iv) companies audited by one of the “Big Four” display higher disclosure levels than those audited by “other companies”. Thus, it is concluded that the characteristics of “size”, “indebtedness”, “corporate governance” and “audit” are factors that affect the dissemination of information about operating segments in Brazil.