Ultrafine RFeO 3 (R Eu, Yb) particles were synthesized by introducing atomized solutions containing metal salts into a high temperature inductively coupled plasma (the spray-ICP technique). The particles exhibited an X-ray diffraction pattern that can be interpreted as an analogue of hexagonal (h) YAlO 3 . They were converted to orthorhombic RFeO 3 at high temperatures above 800°C, and hence can be regarded as metastable compounds. Transmission electron microscopy revealed that the particles are hexagonal platelets 10-50 nm in width. Mossbauer spectroscopy indicated that the iron is trivalent with two different sites, suggesting that the structure is slightly different from that of h-YAlO 3 in the site number of iron. Magnetic susceptibility measurements in the temperature range 4.2-300 K showed that they satisfy paramagnetic moments of the Curie-Weiss law with the trivalent iron and rare earth ions.