After the global financial crisis in 2007 and 2008, there were shortcomings in the regulatory aspects. Basel Committee, a subsidiary of the International Settlements Bank, prepared the draft agreement which in accordance with Article VIII of the Basel 3 banking supervisors must be assured that banks have credit risk management process in which institution\'s risk situation is considered. The purpose of this research is practical, this study did not examine reasons and only models and methods are discussed in this paper. The research method is correlation method. All corporate customers of credit facilities and national banking network that have received credit facilities from National (Melli), Nation (Mellat) and Business (Tejarat) banks are defined as statistical population. The sample size is 370. Each of these banks in the sampling method considered as an organization. In the next step, several branches of different banks are selected by using simple random sampling and in the last stage by applying stratified random sampling, some firms which receiving credit from the banks in the years 2000 to 2010 were selected. The required data were collected by using library and field research methodology. In this study, the descriptive statistics methods and analysis and inferential statistical methods also were used. To investigate credit risk measurement models, significant correlation coefficients test, Coefficients of the linear probability model (bivariate regression and multiple regressions) and ANOVA were applied.