The inclusion crystal formation of naphthalenophanes with polar substituents was investigated in comparison with that of naphthalenophanes without substituents. In contrast with the latters, the naphthalenophane with two methoxycarbonyl groups (2a) afforded rather stable inclusion crystals, in which the benzene molecules were accommodated in the channels along the b-axis. The formation of the channels is ascribable to the strong intermolecular dipole-dipole interaction between the methoxycarbonyl groups. On the other hand, no inclusion crystals were obtained from the naphthalenophane with four ethoxycarbonyl groups (2b).