Various oxygen carrier particles have been developed for chemical-looping combustion(CLC), in which metallic oxide medium is reduced by fuel in a reduction reactor and reduced metal is oxidized by air in an oxidation reactor. This system may yield great advantage of savings of energy and suppressing the effect on environment. In this study, carbon deposition characteristics of three oxygen carrier particles(NiO/bentonite, NiO/NiAl2O4, CoxOy/CoAl2O4) for syngas fueled CLC have been investigated by using TGA(thermo-gravimetric analyzer) from the viewpoints of maximum conversion and degree of carbon deposition. By doing this, we could clarify appropriate reaction conditions to avoid carbon deposition in cyclic reaction and draw up a carbon deposition free map.