In order to improve the performance of boundary layer ceramic capacitors (GBBLC), BaTiO3 powder coated with CuO was prepared by heterogeneous co-precipitation method, B2O3 and MgO were added to improve the performance of the samples, and a series of samples were prepared according to the preparation process of ordinary electronic ceramics. The density and volume shrinkage of the samples were tested, the microstructure of the samples was analyzed, and the dielectric constant and dielectric loss characteristics of some samples were discussed. The results show that the compactness of the sample is significantly improved, the maximum volume shrinkage rate exceeds 40%, the dielectric constant exceeds 7×104, and the dielectric loss is also significantly reduced. CuO and B2O3 have obvious sintering effect, the sintering temperature can be reduced to 1 100 °C, MgO can improve the performance of the sample, so that the porosity is significantly reduced, and the dielectric properties are also obvious