The invention provides a high-hardness, wear-resistant and corrosion-resistant alloy of an amorphous / nanocrystal matrix and a preparation method of the high-hardness, wear-resistant and corrosion-resistant alloy. The high-hardness, wear-resistant and corrosion-resistant alloy of the amorphous / nanocrystal matrix comprises the following elements in percentages by mass: 9.0-12.0 of Cr, 2.6-2.9 of B, 0.7-0.9 of C, 0.4-0.8 of Nb, 0.4-0.8 of V, less than 0.3 of Mn, less than 0.07 of Si, less than or equal to 0.01 of S and P, and the balance of Fe, wherein the sum of C and B is 3.3-3.6; the content ratio of C / Cr is 0.06-0.08; and the sum of Nb and V is 0.5-1.0. Through multi-component alloying, an eutectic composition is formed, the melting point is low, fluidity is good, requirements of a casting technology are simple, large wear-resistant and corrosion-resistant castings can be cast, and small precision wear-resistant and corrosion-resistant castings can also be produced. The hardness of the alloy is HRC66-70, and impact toughness of the alloy is 4-9 J / cm (2).