According to the crystal symmetry and crystallization habits of the alpha-NiSO4 . 6H(2)O(alpha-NSH) crystals, cylindrical shaped alpha-NSH single crystals with a diameter of 30-40 mm and length of 40 mm have been grown by directional crystallization from a cooling solution. The measurements of X-ray diffraction and transmission spectrum have shown that the grown single crystal belongs to the tetragonal system with the space group of P4(1)2(1)2, and it has excellent optical properties.