Cyclophane derivatives were irradiated with an ArF excimer laser in the gas phase. No triplet states, fluorescence, or cation radicals were observed in the transient spectra. The CH2-CH2 bonds dissociated, forming corresponding xylylenes by a two-photon process. The bond dissociations were explained in terms of a multiphoton reaction of hot molecules formed by an internal conversion. In addition, a slow rise of xylylene that originated in the single photon dissociation process of hot cyclophane was observed in the case of methyl-substituted paracyclophanes under low pressure conditions. The specific reaction rates of the dissociations of highly strained paracyclophanes were well explained by a statistical reaction theory, if a simple consideration of strain energy was made in the calculations.