The results of a Monte Carlo simulation for adsorption from solutions of monomers and dimers on heterogeneous surfaces are presented. The adsorption and orientation of dimers adsorbed on surfaces of different (striplike and chessboard) topography are discussed. It is demonstrated that the surface topography has a considerable effect on the adsorption and orientation of dimers only when the size of the homotatic domains is smaller than the length of the adsorbed rodlike molecules. For larger patches, the adsorption does not depend strongly on the surface topography.