According to molecular formula YBa₂Cu_2.7Ag_0.3O_7-δ(YBCAO), we have prepared bulk superconducting samples by solid state reaction method. In order to investigate the effect of Ag₂O addition on the property of YBCO, the measurment of the temperature dependance of resistance, XRD and SEM have been used respectively. The results show that the grains become smaller and the superconducting stability is strengthened. In this paper, the results are discussed.