Magneto-optical crystal YFeO3 has been grown by optical floating zone method. Some key issues on crystal growth, such as feed rod, growth rate and annealing process, have been discussed. It was found that the stability of the melt was seriously affected by the diameter, the density and the homogeneity of the feed rod. The dense and uniform feed rods with pure phase were prepared by complete mixing and repeated sintering at a suitable temperature. YFeO3 crystal up to Φ10 mm × 40 mm was obtained by the optimizing growth conditions: the diameter of the rod was less than 10 mm, the growth rate was about 3～5 mm/h, and the furnace was slowly cooled down after the growth finished. The refractive indices and extinction coefficients of YFeO3 crystal were measured by means of ellipsometric spectroscopy. YFeO3 crystal shows high refractive indices.