The banking sector is one of the most important economic sectors in each country. The total loan repayments of banks are their most important asset, and interest on loans is a major part of the banks' income. Meanwhile, the reason for the accumulation of a large volume of bank liens is a noteworthy point. This study attempts to analyze the determinants factors of non-performing loans in the Iranian banking sector. For this purpose, using panel data and STATA and Minitab software from 1386-1392 (18 banks). We find that in the case of Non-performing loans, bank capitalization, size, and ROE variables have a significant impact on non-performing loans.