Abstract: At present，biodiesel is mostly used as biodiesel-diesel blends. The properties of blends are important for the storage，transport and usage of blended fuels. The density，sulfur content，kinematic viscosity，cold filter plugging point and flash point of Jatropha curcas L. oil biodiesel -diesel blends were studied. The density of blends was linear with the volume content of biodiesel，and the sulfur content of blends decreased with the increase of biodiesel in a linear relationship. The equation ln(υρ)=v₁ln(υ₁ρ₁) +v₂ln(υ₂ρ₂) was used for predicting kinematic viscosity of the blends. Flash point increased slowly when the content of biodiesel was below 40%，whereas it increased sharply with the increase of biodiesel over 40%，especially over 70%. There was no change in cold filter plugging point of blends as compared to Jatropha curcas L. oil biodiesel and 0^# diesel.