In order to design a rotor blade cooling structure in turbo shaft engine,a set of turbine heat transfer design process was applied,and measures to improve the pipe network calculation in accurately simulated flow in tip of blade were proposed. The results show that the flow rate difference between pipe network and the aero-thermal conjugated calculation is about 8. 8%,while the difference of average temperature is about 10. 1%. Pipe network has the function of program design,the difference of average temperature between pipe network and three-dimensional temperature field calculation is about 7. 6%. Three-dimensional temperature field calculation has the function of analyzing the detail of temperature after pipe network. By using this design process the blindness of designing cooling structure can be reduced and design of cooling structure will be more flexible. After improving the method of adding boundary in pipe network,intrusion has not occurred,flow rate in the first dust hole is 0. 715 g / s,while in the second dust hole is0. 139g / s,the flow rate in trailing edge split is 1. 935g / s. By improving the method the accuracy of pipe network calculation can be promoted.