Abstract: The effect of and trace Ce on the microstructure and tensile properties of T8 aged and T6 aged 2195 aluminum-lithium alloy had been studied by tensile tester, transmission electron microscopy and scanning electron microscopy, etc. The results show that the addition of Ce could significantly improve the microstructure and mechanical properties of heat-treated 2195 aluminum alloy. The trace Ce could increase the amount of the major strengthening phase of T1 and θ′ phase and make them distribute more dispersively and homogenously. On the other hand, Ce could refine the grain size, purify the grain boundaries, restrain the recrystallization and make the microstructure delamination of the alloy thinner, which could improve the fracture behavior of alloy and decrease the tendency of intergranular fracture in a certain degree.