Cu2ZnSnS4 thin films have attracted much attention due to their abundant elemental crust content, non-toxic and excellent photoelectric properties. In this paper, Cu2(CdxZn1-x)SnS4 (CCZTS) thin films were prepared by partially replacing Zn with Cd based on nano-ink method. The effects of annealing time and post-annealing temperature on the properties of the thin films and solar cells were studied. The results show that the prepared thin films are CCZTS phase without other heterogeneous phases, and the surface of thin films is flat and dense with good crystallinity. With the increase of annealing time, the grain size of thin film increases, the quality of pn junction of the thin film solar cells is improved, and performance of the solar cells is also improved. The effect of elemental diffusion in the absorber layer on the performance of solar cells after post-annealing was analyzed, and the performance of solar cell was improved when Cd elements formed a gradient distribution. With the increase of post-annealing temperature, both of the solar cell performance and pn junction quality first increase and then decrease. The solar cell conversion efficiency is optimal (3.13%) after 300 ℃ post-annealing treatment.