Growth conditions were studied for three types of non-isoaxial bicrystals of an Fe-3mass%Si alloy characterized by different combinations of low-index growth axes of the adjacent crystals, i.e., [1 0 0]/[1 1 1], [1 0 0]/[1 1 0], and [1 1 0]/[1 1 1] with grain boundary planes {0 1 1}, {0 1 1}, and {1 1 2}, respectively. Among these combinations, only the [1 0 0]/[1 1 1],{0 1 1} bicrystals 13 mm in diameter and up to 40 mm long were successfully prepared by the floating zone melting technique. The success of the growth depends primarily on the mosaic substructure of both component crystals in growing the bicrystal.