Contagious ecthyma is a viral infectious disease that produces pustular vesicular rashes on the skin and mucosa, affecting a wide range of species, goats, sheep, wild ruminants, even carnivores and human. In this paper, it were investigated the strains of Staphylococcus aureus, isolated from a contagious ecthyma outbreak, from the lesions caused by this virus in 5 flocks of sheep in 3 hotbeds of the disease. Attention was paid to the exact establishment of the type of isolated Staphylococcus, and the assessment of the antibiotic sensitivity by performing the antibiogram (CLSI, 2012). The results of the antibiogram showed an increased sensitivity to the action of Gentamicin (96,6%) and of quinolones (ciprofloxacin 86.6%, enrofloxacin 83.3%), even of trimethoprim (80%). Staphylococcus aureus is a ubiquitous germ, the cases of antibiotic resistance encountered due to the unusual use of antibiotics are frequently recorded in this germ. The increase of the penicillin resistance phenomenon, widely used in the past, has led to new generations of antibiotics in this group (semi-synthetic penicillin). Based on the sensitivity of the strains of Staphylococcus aureus isolated in 7 types of antibiotics, it was computed the MAR index (multiple antibiotic resistance index), in order to establish the risk degree represented by these types of strains for animals and humans. The values of the MAR index were between 0,14 and 0,57, in 63,3% of the cases the value exceeding the limit of 0,2, showing the possibility of the occurrence of the multiple antibiotic resistance. Moreover, the values over than 0,2 also show the fact that antibiotics are frequently used in the outbreaks of the disease investigated.