The objective of this work was to study the protein patterns, plasmid profiles, and antibiotic susceptibility of Staphylococcus intermedius and Staphylococcus aureus isolates originating from mastitic mammary glands of dairy cattle in different parts of Konya province. A total of 114 Staphylococcus species were isolated and identified by conventional bacteriological methods from bovine mastitis. Of the total isolates 77 were identified as S. aureus and 37 as S. intermedius. Intraand inter-species diversities in the coagulase-positive staphylococci were investigated by analysis of whole-cell protein profiles using sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). Plasmid profiling also demonstrated that 75 S. aureus isolates and 36 S. intermedius isolates contained plasmid. In addition, 88.3% of S. aureus and 59.4% of S. intermedius isolates were resistant to penicillin. Sixty-six of the 77 S. aureus isolates were also resistant to amoxicillin+clavulanic acid (85.7%). The corresponding number for S. intermedius was 17 (45.9%). Only 1 S. aureus isolate was resistant to danofloxacin. One of each of the Staphylococcus isolates was resistant to methicillin. Results from the study showed that the susceptibility of S. intermedius isolates to antibiotics used widely in mastitis therapy is a matter of concern. © TÜBİTAK.