BaFe12O19 (BaM) powders and their corresponding ceramics were prepared by the sol–gel method at different solution concentrations (0.195–0.325 mol/L). The effects of solution concentration on microstructure, surface morphology, electrical properties, and magnetic properties of BaM powder BaM ceramics were systematically studied. XRD results show that the powders are pure BaM phase. SEM results show that with the increase in solution concentration, the grain size of ceramic increases, and the grain size of hexagonal sheet structure decreases gradually. At room temperature, when the solution concentration is 0.195 mol/L, ceramics' saturation polarization intensity and residual polarization intensity reach the maximum, which are 0.528 μC/cm2 and 0.297 μC/cm2, respectively. When the solution concentration is 0.325 mol/L, the ferroelectric properties of ceramic deteriorate due to the influence of leakage current. The ferroelectric hysteresis loop and magnetic hysteresis loop of ceramics show the multiferroic properties of ceramics at room temperature, which provides a new choice for single-phase multiferroic materials and lays a foundation for the multi-functionalization of BaM devices. © 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.