Staphylococcus hyicus subsp hyicus (coagulase-positive) was isolated in pure culture from the left coxafemoral and right shoulder joints of a 4-week-old pig with septic polyarthritis. Present taxonomic criteria and DNA-DNA hybridization studies with reference strains were utilized to identify the isolate. There were no clinical signs or generalized skin lesions of porcine exudative epidermitis noticed in this pig.