The detailed conformational analysis of a polymeric system containing a benzene inclusion is presented. Monte Carlo simulations of several polymeric systems, based on polyethylene, PE, have been used in order to investigate the structural perturbation induced in the polymeric matrix by the presence of the benzene molecule. Polymeric chains with different degrees of rigidity have been simulated, and the structural parameters have been compared with their analogue systems without the inclusion of benzene. An initial study performed on conventional PE showed that, thanks to its high flexibility, PE was able to accommodate the benzene inclusion, keeping the conformation of the chains virtually unaffected by the presence of the aromatic ring. The perturbation induced by the ring is an approximately ellipsoidal region centered on the inclusion and of a thickness of about 2 Angstrom. In this region a greater occupancy of mers is found. This perturbation relaxes, in a nonmonotonic way, with increasing distance from the benzene. When higher chain rigidity is imposed, the polymeric chains accommodate the ring by modifying their conformations, mainly through an increase in the number of gauche states. The conformational perturbation induced by the benzene was found to become much stronger, showing the polymeric chains less favorable interaction with the benzene. It is worth to mention that the persistence length of the systems containing the benzene, in the cases where extra rigidity is imposed, is reduced as compared with their analogue systems without the ring. As consequence, it was possible to conclude that even in the absence of any specific interaction between the benzene and the polymeric matrix, the rigidity of the chains plays an important role in the affinity between the benzene and the polymer and in the flexibility of the whole composite.