Pb(Mg${}_{0.5}$W${}_{0.5}$)O₃–Pb(Ni${}_{1∕3}$Nb${}_{2∕3}$)O₃–Pb(Zr${}_{0.5}$Ti${}_{0.5}$)O₃ (PNN–PMW–PZT) piezoceramics were sintered at a low temperature of 900^°C by the mixed metal oxide powder solid-state reaction route. CaCO₃ and Li₂CO₃ as sintering aids and Yb₂O₃ as a dopant were added into the PNN–PMW–PZT ceramic system for low-temperature sintering and enhancement of electrical properties, respectively. The effects of different Yb₂O₃ doping amounts on the microstructure, dielectric, piezoelectric and ferroelectric properties of the samples were systematically investigated. The piezoceramics doped with 0.1$$mol% Yb₂O₃ have optimal electrical properties ($d_{33}=563$$$pC/N, $k_p=0.66$, ${\epsilon }_r=2728$ (1$$kHz), $tan\delta =0.0176$ (1$$kHz), and $T_C=301^{°}$C). While the piezoceramics doped with 0.3$$mol% Yb₂O₃ have optimal energy conversion properties: the piezoelectric voltage coefficient $g_{33}=26.7\times 10^{?3}$$$Vm/N and the effective piezoelectric energy conversion coefficient $d_{33}\times g_{33}=14366\times 10^{?15}$$$m²/N.