Ethnic Korean onggi earthenwares were fabricated using different clay formulations and glazing treatments. Their permeability properties against oxygen, carbon dioxide, and moisture were measured at $20^{circ}C$ and examined from the aspect of food preservation. Onggi walls consisted of micropores that offered higher gas and moisture permeation rates when compared with other food packaging materials. Earthenware walls were unique in having $CO_2/O_2$ permeability ratios of 0.60-1.00. Gas and moisture permeabilities were lower, with wall structure having lower porosity and surface glazing. Results revealed onggi jar packages of grape fruits could attain wide range of $O_2$ and $CO_2$ concentrations. Onggi containers present good opportunity to obtain optimum packaging conditions for respiring or ripening products, depending on commodity type.