The rupture behavior of electron beam physical vapour deposition(EBPVD) Ni/Ni_3Al microlaminates composites subjected to tensile load were studied through the numerical method of finite element. 2D model and 3D model of EBPVD Ni/Ni_3Al microlaminates with a centre crack were built respectively. A new scheme for building 3D crack point models was proposed and different types of elements were used. And stress intensity factors around the tip of the crack were obtained correspondingly. The results indicate that the key of the stress intensity factor for 2D model is presumably the average of the keys for 3D model in thickness and the key at the interface is the biggest, which suggests the propagation of the crack greatly likely happen at the interface. The rupture behavior of electron beam physical deposition deposition (EBPVD) Ni / Ni_3Al microlaminates composites subjected to tensile load were studied through the numerical method of finite element. 2D model and 3D model of EBPVD Ni / Ni_3Al microlaminates with a center crack were built respectively. A new scheme for building 3D crack point models was proposed and different types of elements were used. And stress intensity factors around the tip of the crack were obtained corresponding. The results indicate that the key of the stress intensity factor for 2D model is presumably the average of the keys for 3D model in thickness and the key at the interface is the biggest, which suggests the propagation of the crack greatly likely happen at the interface.