In this work we employ the state of the art pseudopotential method, within a generalized gradient approximation to the density functional theory, to investigate the interaction process (i.e. adsorption and dissociation) of cyclic hydrocarbons (cyclopentene, cyclohexene, and 1,4-cyclohexadiene) with the silicon (001) surface. Our first-principles calculations suggest that all considered cyclic hydrocarbons are adsorbed on the Si(001) surface via a [2+2] cycloaddition reaction with adsorption energies of 35, 23, and 31 kcal/mol for cyclopentene, cyclohexene, and 1,4-cyclohexadiene, respectively. Possible reaction pathways for the dissociation of the methyl radicals and the breaking of the Si-Si dimers of the surface are considered. In addition, we present theoretical STM images of possible adsorbed systems, with a view to contribute to further experimental investigations.