For the purpose of examining the possibility of promoting the aromatization of ethane in the presence of carbon dioxide, the reaction of ethane and carbon dioxide on Ga-, Zn- and Pt-loaded HZSM-5 catalysts were conducted. The catalytic test on Ga-HZSM-5 revealed that the introduction of carbon dioxide improved the formation of aromatics, in particular, the aromatics formation from ethylene consisting of oligomerization of ethylene and dehydrocyclization of alkenes. The strength of adsorption of ethylene and carbon dioxide were approximately equal in magnitude on Ga2O3. On the other hand, carbon dioxide preferentially adsorbed on ZnO, and so did ethylene on Pt/SiO2, respectively. Although the hydrogen consumption through the reverse water-gas shift conversion improved in the catalytic run on Ga-HZSM-5-V2O5 composite catalyst, the yield of aromatics and the selectivities of ethylene and aromatics remained essentially unchanged. These results indicate that the balance of strength of adsorption of both substrates on metal species is significant in order to promote aromatization of ethane in the presence of carbon dioxide, and that promotion of aromatization by the introduction of carbon dioxide is not attributed to thermodynamic effect, but to kinetic effect.