0.7BiFeO₃–0.3BaTiO₃ + 1 mol % MnO₂ + x mol % Co₂O₃ multiferroic ceramics were fabricated by an ordinary sintering technique and the effects of Co doping on the microstructure, multiferroic and piezoelectric properties of the ceramics were studied. All the ceramics possess a pure perovskite structure with rhombohedral symmetry. The addition of a small amount of Co₂O₃ enhances the ferroelectricity, ferromagnetism, piezoelectricity and temperature stability of the ceramics. The ceramic with x = 1.0 possesses enhanced piezoelectricity (d₃₃ = 134 pC/N), good ferroelectricity (P_r = 19.9 µC/cm²) and increased high depolarization temperature (T_d = 475°C). The 1 mol % Co₂O₃ doping greatly improves the ferromagnetic property of the ceramics and the optimum remnant magnetization M_r of 0.191 emu/g of the ceramic is obtained at x = 1.0. These results show that the ceramic with x = 1.0 is a promising candidate for lead-free high-temperature piezoelectric and room-temperature multiferrioc materials.