This paper mainly studied the spray characteristics of gasoline-biodiesel blends(GB)injected with the common rail injection system of diesel engines.The experiments including fuel properties,phase separation and spray characteristics of gasoline-biodiesel blends were performed.At first,the chemical and physical properties of biodiesel blended with commercial gasoline with the concentration of 0,5,10,15 and 20%name as GB00-GB20 by volume were investigated.Neat gasoline,biodiesel and diesel were also tested as the reference.The effects of biodiesel on viscosity,density,lubricity,cloud and pour point were measured.Secondly,phase stability was carried out by varying biodiesel concentrations and ambient temperature.Consequently,the GB00-GB20 were performed on spray macroscopic visualization test.The shadowgraph technique was conducted in the constant volume chamber and recorded by a high speed video camera with frame speed 10,000 f/s.Fuel injection pressures were set at 1,000,1,200 and 1,350 bar at simulated engine speed 2,000 rpm.The constant back pressures were set at 30 and 50 bar.The spray angle and spray penetration tip were measured and analysed by image processing technique.The results showed that lubricity of the blends significantly increased when biodiesel concentration increased.Biodiesel mixed homogeneously with gasoline for all concentrations at 25℃.However,phase separation appeared as the crystalline colloids when ambient temperature was below 5℃.The spray penetration length increased when injection pressures were increased.Also,spray cone angle slightly decreased.There is slightly difference of spray angle and penetration length between GB blends.