A novel model with built-in tungsten filament on the basis of join W/Cu functionally graded layer was proposal and investigated.Using the ABAQUS software on the basis of finite element method,the distributions of temperature and thermal stress in different first wall panel models under normal ITER operation condition are simulated.The result shows that the novel model significantly reduces the high thermal stress in the interface of tungsten armor and copper layer.To achieve the optimal design of this model,four independent simulations with different conditions were performed to determine effects of the interval of tungsten filaments,the neutron heating and the thickness of W armor,and W/Cu functionally graded layer.