Growth of various kinds of eutectic fibers based on Al2O3 and oxides of Y and rare earths from Sm to Lu using micro-pulling-down (mu-PD) method was investigated. The effect of rare-earth element substitution on growth, microstructure and mechanical properties are discussed, Eutectic materials were classified into Al2O3/garnet system and Al2O3/perovskite system types at the boundary between Gd and Tb. Al2O3/garnet eutectic fibers showed superior high-temperature strength properties. This is the first systematic study of the characteristics of these eutectic materials.