Аннотация:A numerical algorithm is developed for the diffraction of an electromagnetic wave on an infinite dielectric cylinder of arbitrary cross section immersed in a free space. The boundary-value problem for the Maxwell equations in a nonhomogeneous space is reduced to solving a system of singular integral equations by the approximation and collocation method. The matrix elements are evaluated by a special numerical algorithm. The evaluation of the singular integrals is reduced to the evaluation of integrals with a logarithmic singularity.