This study aimed to test the influence of non performing loans, quality assets, liquidity, and rentability towards the capital adequacy ratio. The data used in this research was the publication of annual financial report of banking registered in BEI during the period 2008-2013. The population in this research was conventional banking companies registered in BEI. Sample method in this study was using the purposive sampling method. Retrieved number of sample was 17 companies. the method of data analysis used in this research was multiplied linear regression alongside with a significant level (α) was 0,05. The results of this research showed that the NPL, liquidity, and rentability partially do not have an influence on CAR. While the quality assets measured using NPA ratio was negatively significant to the CAR.