At present, the multi-material fusion 3D printing technology has a good application prospect for the development of short-life and low-cost small engines, such as the application of 3D printing functionally graded materials in the typical hot section parts of new-type turbine disk. In order to explore the influence of pore defects generated by 3D printing technology on the burst speed of turbine disk in aero-engine, the burst speed analysis of functionally graded material validation turbine disk was carried out based on the strain-based fracture criteria under the testing uniform temperature field of 500 ℃ and the real temperature field respectively. Our studies mainly focus on the influences of pore defect characterization parameters and related factors, such as porosity, the position of large pores located, the number of large pores, large-pore spacing and the distance between large pore and bursts initiation position on the burst speed of validation turbine disk. The results show that the random distribution of pore defects is not the only consideration for the performance analysis of 3D printed disk. The large pores distributed in the high-strain region (hazard section) will lead to a significant decrease in the burst speed of validation turbine disk, and the defects in the high-strain region, close to the predicted bursts initiation position, should be strictly controlled during 3D printing.