Previously, we reported on the antibiotic resistance patterns of 50 strains of Staphylococcus aureus which were isolated from a hospital in Busan, Korea from July 2005 to December 2006. We have isolated small plasmids and classified plasmid types by agarose gel electrophoresis. We have selected 5 plasmids and determined complete nucleotide sequences of those plasmids. The aim of this paper is to report on the characteristics of cadmium, erythromycin, lincomycin resistance plasmids and a cryptic plasmid based on the sequence analysis obtained by using the BLAST program.