Abstract: Bio aviation kerosene was prepared from soybean oil by catalytic cracking, distillation, aromatization and hydrogenation, and its composition and physicochemical properties were analyzed. A piston aero-engine was used to start the bench test, and the applicabilities of bio aviation kerosene and RP-3 fuel were compared and analyzed. The results showed that the basic components of bio aviation kerosene were straight-chain alkanes 74.54%, naphthenes 13.04%, aromatic hydrocarbons 10.31%, ethers 1.07% and non-alpha-chain olefins 1.04%. The calorific value of bio aviation kerosene was high(44.4 MJ/kg), freezing point was low(-48 ℃), but its viscosity was high(2.11 mm²/s). Compared with RP-3 fuel, bio aviation kerosene had lower start-up temperature; temperature rise rate(within 4 ℃ difference), fuel consumption(less than 0.02 g/s difference) were close to those of RP-3 fuel, the excess air coefficient fluctuated greatly(0.8-1.2) when engine speed exceeded 4 200 r/min, and those of combustion state deteriorated; engine disassembly inspection after bench test showed that coking occured after burning bio aviation kerosene. The phenomenon of carbon deposition was due to the high viscosity(>2 mm²/s) of bio aviation kerosene in this batch, which had an impact on the working performance of engines such as atomization efficiency and combustion adequacy.