Piezoelectric properties and thermal stability of tetragonal-structured (Ba0.838Ca0.162)(Ti0.908−xMnxZr0.092)O3 (0.46BZT–0.54BCTMn) compositions away from morphotropic phase boundary (MPB) were investigated. The results demonstrated that the addition of small amounts of Mn did not cause a remarkable change in crystal structure, but resulted in an evident evolution in piezoelectric properties and thermal stability. Mn could induce combinatory hard and soft piezoelectric characteristics due to aliovalent substitutions and improve thermal stability. The optimal electrical properties were obtained in the modified composition at x=0.006 with piezoelectric constant d33=410pC/N, planar electromechanical coupling factor kp=0.40, mechanical quality factor Qm=150, remnant polarization Pr=14.1μC/cm2, coercive field Ec=4.44kV/cm and a high Curie temperature Tc~99°C, respectively. It can be expected that the improved piezoelectric material can be a promising candidate for lead-free piezoelectric applications.