After thirty years adoption and implementation of Law of banking operations without Reba , is an opportunity to evaluate the new banking system. Theoretical and practical aspects of the new system shows gaps and many problems that can be corrected and completed, effective steps taken to streamline the system. Banking industry by equipping and directing the savings towards productive economic activities are created an important role in the economy are created. As long as development of the banking industry, Muslim thinkers have tired to using this phenomenon, But they found that most of the bank activities are based on interest and Reba ,are forbidden by Islam, so tried to maintain normal banking operations and discover legal justifications but they could not find the one which is acceptable by religious scholars.  It was the turning  point some Islamic scholars to design a bank based on Islamic principles, the result   was manifested in the form of Islamic banking. Islamic banking is growing quickly, especially in recent years.The rapid rate of growth that is observed with increasing demand among Muslims in Islamic banking, growth in oil revenues in the Middle East and attraction of  financial Shariatmadar services for investors seeking ethical banking activities, is reliable. Now, Islamic banking, was established in 75 countries, a considerable part worldview shapes the economy sight among the countries of Iran, Malaysia, Saudi Arabia and the United Arabic Emirates are the greatest assets in accordance with the shariat. On the other hand, after the financial and economic crisis in the world economy in countries with free economy, many Economic experts believe that Islamic banking with its unique features can proper and safe alternative to conventional banking, Islamic banking should be noted that the system seen as a developing reality This experience should be evaluated neutral and  for continues growth its problems should carefully be reviewed.The present study is an attempt to describe the Islamic banking and a comprehensive review of the most important current problems of the Islamic banking system in Iran