Lean combustion in spark ignition engine has been recognized as mean of both improving engine efficiency and lowering exhaust emissions. However, combustion stability of this combustion has been challenging. Misfiring due to improper mixture strength in lean operation may be occurred. There are various parameters related to stability on lean combustion such as swirl or tumble flow intensities, ignition timing, spark energy and fuel properties. In this study, effect of ethanol concentration, E0, E20, E85 and E100, on lean limit were experimentally investigated in various swirl intensities by using a constant volume combustion chamber. Coefficient of variation (CoV) and combustion pressure data were observed and analyzed by using high resolution pressure transducer. Experimental results show that the lean limit of gasoline (E0) can be extended by using higher percentage of ethanol content and higher swirl intensity. In addition, high swirl intensities direct injection ethanol fuel combustion can achieve the stable lean combustion along with low cyclic variation due to the mixture stratification in the chamber. The cyclic variation decreases with ethanol concentration and swirl flow intensity.