Abstract: The characteristics of the flow through the small turbine components were analyzed in detail based on the mission and operating conditions.It was shown that the effect of boundary layer and secondary flow,including passage vortex,trailing vortex and tip clearance flow,etc,was remarkable.This was determined by the small-scale and high rotating-speed as the basic features of small turbine.By investigating the aerodynamic design ideas and concrete methods of small turbine component,a new turbine for a small turbofan engine with the thrust of 1000daN was designed.The results of 3-D viscous numerical simulation show that,the turbine meets the design requirements with high efficiency.