This study aims to analyze the differences between the financial performance of islamic banks and conventional banks seen from the capital ratio, profitability ratios, liquidity ratios and efficiency ratios. The sample in this research is 3 islamic banks and 27 conventional banks with the study period from 2006 to 2009. The method used in sampling is purposive sampling and analytical methods used are different test independent sample t-test with significant level 0.05. The results of this study concluded that there are significant differences between Islamic banks and conventional banks seen from the capital ratio, profitability ratios and liquidity ratios with significant value equal variances not assumed 0.000, 0.001, 0.001 < 0.05. And there is no significant difference between Islamic banks and conventional banks seen from the efficiency ratio with significant value 0.198 > 0.05.