CO2 reforming of CH4 catalyzed by porous SiO2 and TiO2/SiO2-supported Ni was studied. Ni on the porous substrates was deposited using atomic layer deposition method, and after the catalytic reactions, Ni nano-particles confined within the pores of the substrates were found. Both catalysts showed comparable catalytic activity and stability. The bare SiO2-supported catalyst showed very stable reactivity for the reforming reaction with an activity loss of similar to 10 % at 850 degrees C during 29 days. Thus, the porous SiO2-supported Ni which is uniformly deposited in interior of the support could be one of the promising catalysts for CO2 reforming of CH4.