Dielectric and electromechanical losses play a critical role in the performance of the transducer in high power conditions. In this study, we report a systematic study on the effect of Mn-doping on the losses in the Pb(Zr (x) Ti1-x )O-3-Pb(Zn1/3Nb2/3)O-3 (PZT-PZN) system. Two types of sintering conditions were employed to synthesize ceramics with varying grain sizes. The Zr/Ti ratio in the PZT system was fixed at 52/48 corresponding to morphotropic phase boundary (MPB) and Mn concentration was varied from 0 to 0.9 wt%. The results show that the composition 0.9PZT-0.1PZN + 0.5 wt% Mn provides optimized magnitude for the dielectric, piezoelectric, and loss properties.