ZK60 alloy strip was fabricated by Twin Roll Casting (TRC for short) technology in this paper. The effect of heat treatment on microstructure and damping capacities was discussed by using optical microscope (OM) and dynamic mechanical analyzer (DMA). The homogeneous structure was obtained after annealing treatment. The equiaxed recrystallized grains were obtained after T6 treatment. The damping peak P1 is a relaxation process. The activation energy H for P1 was 132KJ/mol. The damping peak P2 is not a relaxation process. It is a recrystallized damping peak. The classical curve of strain amplitude dependence of damping capacity of TRC ZK60 strip was present after T6 treatment (aging for 6hrs), but the curves of strain amplitude dependence of damping capacity of TRC ZK60 strip with two different dislocations system were obtained after the other T6 treatment. Strain amplitude dependence of damping capacity of TRC ZK60 strip after T6 treatment abide by the G-L theory.