In this work,a theoretical analysis of plasmonic enhancement of Ag particles embedded in CaTiO_3thin-film layer for ZnO structure solar cells is presented.Due to the introduction of Ag particles, the absorption of solar cell is enhanced,owning to the strong surface plasmon absorption of Ag pa rticles and synergistic effect between Ag and CaTiO₃.In our analysis,the optimized radius of Ag particles is 80nm.The average absorption efficiency of the optimized nano-structure can achieve 80%,which is 24% higher than that of pure CaTiO_3thin- film layer structure.We believe the proposed Ag/CaTiO_3solar cells structure c ould be a potential candidate for futureindustry manufacture with low-cost and simple fabricationprocess.