Blades with excellent high temperature performance are increasingly required with the development of industrial gas turbine.Industrial gas turbine blade exhibits complex shape and thickness as well as thin-walled structure with complex cavity in blade body

which results in the inevitable occurrence of shrinkage porosity（hole） in the blades.In order to investigate the defect formation and to optimize the processing parameters

the fluid field and temperature field are simulated by the FEM to predict the formation of shrinkage porosity（hole） during solidification process.The results show that confluence of liquid alloy occurs at the middle of pressure side

resulting in the formation of gas entrapment.The ingate on top of the tenon solidified in advance as a result of thin wall and blocked the feeding channel between the riser and the bottom of tenon

leading to the occurrence of shrinkage porosity（hole） in the tenon as well as in both gating systems.The practical experiment was conducted.The results are well in agreement with the simulated ones in shrinkage porosity and gas-entrapment.To eliminate the defects

the larger ingate was designed at the proper location to improve the gating system.