This study was done due to provide empirical facts from the effect of Financing to Deposit Ratio (FDR), Non Performing Financing (NPF), Bank Size, Gross Domestic Product (GDP), and Inflation on the efficiency of Indonesian Islamic Banking. This study used secondary data from the annual financial statements of Islamic Banks, with verification research methods. To measure efficiency this study used the Data Envelopment Analysis (DEA) method with DEAP software version 21. The research sample was determined by using purposive sampling technique. The sample selected was 12 General Islamic Banking. The period used 2014 to 2018. Analysis of the data used is regression analysis panel data with Eviews Version 10. Based on the results of efficiency measurements of 12 General Islamic Banking shows a fluctuating trend, and only one General Islamic Banking experiences efficient conditions throughout the research period, while the results of the hypothesis analysis be concluded that FDR and Bank Size have a significant positive effect, while NPF, GDP, and Inflation have a significant negative effect on the efficiency of Islamic Banking.