The effect of phosphorus additions on the structure, microstructure and dielectrics properties of the Pb_0.98Ca_0.02[(Zr_0.52Ti_0.48)_0,98(Cr³⁺_0.5, Ta⁵⁺_0.5)0,02]_1-xP_x O₃ (x ranged from 0.01 to 0.12) ceramics have been investigated. All of the samples were prepared by a high-temperature solid-state reaction technique. AFM analysis of the compounds suggests that the average grain size increases with increasing sintering temperature which is characteristic of a ceramic material. Until that it reaches maximum values for the simple doped with 4 Wt. % of P₂O₅ at a sintering temperature of 1050 °C. Dielectric studies of the compounds as a function of frequency (from 1 to 200 KHz) sintered at different sintering temperatures (1000, 1050, 1100, 1150 and 1180° C) show that the compounds undergo a phase transition of diffuse type. The transition temperature shifts towards higher side with increase in frequency a typical characteristic of a relaxor material.