The purpose of this study is to investigate the effect of the temperature variation and blending ratios on fuel properties of biodiesel and biodiesel blended with ethanol fuel. Adding the ethanol to biodiesel fuel can be improved the disadvantage of cold-starting of biodiesel fuel. Furthermore, properties which depend on the change of fuel temperature affect the spray behavior, combustion and emission characteristics in combustion chamber. The kinematic viscosity and density were obtained by the measured dynamic viscosity and specific gravity, respectively. In this study, it was revealed that the specific gravity and density decreased linearly when the fuel temperature and the ethanol blending ratio increased. Empirical equation can be derived from the measured values and it is the function of the second order of blending ratio and the first order of fuel temperature.On the other side, the dynamic and kinematic viscosity decreased exponentially as rising of the fuel temperature. Based on the measured value of viscosities, the empirical equation which is the function of fuel temperature can be derived at each ethanol blending fuels.