The micro-pulling down method has been applied to grow A1(2)O(3)/ZrO2 eutectic fibers and to investigate their microstructural properties as a function of solidification rate. Al2O3/ZrO2 eutectic fibers 0.2 similar to2 mm in diameter and 500 mm in length have been grown with a pulling rate of 0.1 similar to 15 mm/min. The eutectic microstructures changed as a function of pulling rate from rod shape to cellular shape containing some thin lamellae. Typical lamellar thickness decreased from about 380 to 110 nm as the pulling rate increased from 1 to 15 mm/min. The interlamellar spacing, 1 fits the inverse-square-root dependence on the pulling rate, v according to lambda = 1 xv(-1/2), where lambda has the dimension of mum and v is in mu /S. Hardness value reached 13.1 GPa for fibers grown at a pulling rate of 15 mm/min and tensile strength of 900MPa was achieved at a pulling rate of 10mm/min, The hardness also increased as the interlamellar spacing decreased.