Abstract:(1–X)BiScO3-XPbTiO3(X=0.60, 0.62, 0.64, 0.66, 0.68) piezoelectric ceramics were synthesized by a conventional solid-reaction method, and their microstructure and piezoelectric/dielectric properties were investigated. XRD results show that there is morphotropic phase boundary (MPB) when X=0.64, the samples are rombohedral phases when X<0.64, and tetragonal phases when X>0.64. The maximum piezoelectric constant of 430 pC/N is obtained with the MPB composition. The dielectric-temperature test results indicate that BiScO3-PbTiO3 system is relaxor ferroelectric and has a very high Curie temperature of 450 oC.