FORTRAN program for a numerical solution of the nonsinglet Altarelli-Parisi equation. We investigate a numerical solution of the flavor-nonsinglet Altarelli-Parisi equation with next-to-leading-order α s corrections by using Laguerre polynomials. Expanding a structure function (or a quark distribution) and a splitting function by the Laguerre polynomials, we reduce an integro-differential equation to a summation of finite number of Laguerre coefficients. We provide a FORTRAN program for Q 2 evolution of nonsinglet structure functions (F 1 ,F 2 , and F 3 ) and nonsinglet quark distributions. This is a very effective program with typical running time of a few seconds on SUN-IPX or on VAX-4000/500. Accurate evolution results are obtained by taking approximately twenty Laguerre polynomials.