Abstract of the article in the journal: Issues of Economics, 2014, No09 - M. : Publishing house of NP "Editorial Board of the journal "Questions of Economics", 2014. 15 s. Many authors believe that increased transparency of the banking system leads to increased competition between banks. To test the hypothesis that disclosure is related to market power and concentration in the banking system, we use data for 213 countries for 2001, 2005 and 2010. The results refute the generally accepted view: countries with a higher level of transparency in the banking sector have a lower level of concentration, and the relationship between information disclosure and market power is weak. Moreover, as the risks of the banking sector increase, the effect of disclosure is growing at a slowing pace. Banking services markets competition. Financial sector regulation strategy . Impact of disclosure on competition in the banking sector. The question of the relationship between mandatory disclosure and banking competition. Data and methodology. Results. Descriptive statistics. Effect of market discipline. Results stability check. Alternative transparency measures . Descriptive statistics of alternative transparency indices. Modified sample. Impact of the monitoring index, checking the stability of the results. Impact of disclosure index, validation of results stability. Impact of transparency index, modified sample, results stability check