Since the main source of finance for the Iranian manufacturing firms is the bank loan, the bank-firm relationship plays an important role in their performance. In effect, firms with decent financial potency regularly have a better chance to access high-quality and less costly finances. In this paper, we investigate the bank-firm relationship and its determinant factors by using a unique database that includes the listed companies’ outstanding loans with the details of the lending banks over the period of 2007-2014. In this regard, the main bank share, number of bank creditors, concentration index, the share of private banks, and length of relationship with the main bank are defined as selected indexes for the bank-firm relationship. According to the research findings, firms with lower liquidity risk and better financial ratio can access the loan with better quality and lower costs. Moreover, the regression results indicate that the share of the private banks’ loan is higher for firms with poor liquidity condition. Moreover, loans in the firms with higher cash flow are more concentrated to a few creditors. In addition, an increase in the size of firms is positively correlated with the share of the private banks’ loan and the number of creditors.