The purpose of this study is to explain the effect of interbank financial relation development as a convergence and integration approach in banking system of Iran by which we will be able to evaluate targeting credit allocation and profitability of banks. In other words، we evaluate this view that by more complication of economic relation which is the result of interdependency of various markets، in addition to strengthening the competitiveness and financial interbank relationship strengthen banking efficiency in optimizing credit allocation and profit increase. Accordingly، an econometric model will be established in which، by using cross-section data of the Iranian in 2008-2011، the effectiveness of interbank financial relation and other factors development on credit allocation and banking profitability will be studied. The results of this study show the most important factors affecting banking profitability and credit allocation improvement in new banking system of the country.