Abstract The effects of co-added Nb and Li additive on phase behavior, densification, microstructure and mechanical properties of Bi0.5(Na0.81K0.19)0.5TiO3composite ceramics were investigated. The samples were synthesized by solid state reaction technique, where powders were calcined at 850 °C for 4 h and ceramics were sintered at 900-1050 °C for 2 h. Phase formation was determined by X-ray diffraction technique (XRD). The X-ray diffraction analysis of the ceramics suggests that all samples exhibited a perovskite structure at low concentration Nb and Li additive. The physical and mechanical properties behaviors slightly changed with increasing the additive contents.