The thermal stress for Al/Ti coatings on uranium substrate was analyzed by using a thermal elastic plastic finite element method (FEM). The results indicate that the thermal stress is compressive inside the Ti coating and tensile inside the Al coating, which reaches the yield strength of Al. There is an uneven thermal stress distribution at the free side of specimen due to the end effect, which is vanished gradually at about 2h (where h is the coating thickness) from the free side of specimen. The shear stress of U-Al at the free side is larger than that in the middle of specimen. The effect of deposition temperature, coating thickness and mechanical properties on the thermal stress and plastic strain in coatings were also investigated. The results show that the thermal stress and plastic strain increase remarkably with the deposition temperature increasing. It is helpful to decrease the thermal stress and plastic strain by decreasing the thickness of Al coating and increasing the thickness of Ti coating. The yield strength of Al coating and the elastic modulus of Ti coating have large effects on the thermal stress and plastic strain of the coatings.