Bi(Ni0.5Ti0.5)O-3 (BNT) ceramics with a perovskite structure, which were almost impossible to fabricate under atmospheric pressure, were synthesized at a high pressure of 6GPa using a multianvil-type high-pressure apparatus. It was confirmed that the synthesized samples had a multidomain structure and ferroelectricity on the basis of scanning nonlinear dielectric microscopy (SNDM) and polarization-electric field (P-E) hysteresis loop measurements.