Lead barium niobate (PBN) presents characteristics as large dielectric and piezoelectric properties around the morphotropic phase boundary (MPB) and the ceramic processing dictates an important role in the enhancement of these properties. In the present paper, we report Raman scattering studies on phase evolution as a function of calcining temperature of the PbO–BaO–Nb2O5 ceramic system. The obtained spectra contributed to the identification of the PBN phase formation kinetics in compositions around the MPB. The results indicated that the increase in the Pb content leads to a lowering of the rhombohedral phase formation temperature with an increase of the orthorhombic phase formation temperature.