The present invention provides an aluminum oxycarbide composition in which the Al4O4C can be inhibited from oxidizing during use and the effect of the Al4O4C can be maintained for a long period. This aluminum oxycarbide composition has crystals of Al4O4C. When any cross-section of the aluminum oxycarbide composition is examined, the crystals of Al4O4C have an average diameter, calculated through conversion of the cross-sectional area of each Al4O4C crystal to a circle, of 20 [mu]m or larger. This aluminum oxycarbide composition can be produced by melting a carbonaceous raw material and an alumina-based raw material in an arc furnace and thereafter cooling the melt in the arc furnace.