Mastitis is one of the biggest expenses for the dairy industry which has a substantial impact on dairy cow health. Preventing new infections in cows is the best strategy to manage mastitis. This study aimed to investigate the effect of a commercially available S. aureus vaccine (Lysigin) on minimizing the rate of mastitis in a dairy herd. A total number of 600 Holstein-Friesian dairy cows were involved in the study and received two doses of the vaccine. The enrolled animals were monitored for clinical signs, bacterial culture, somatic cell count (SCC), and costs utilized for treatment during the study. The rate of clinical and subclinical mastitis after vaccination was reduced from 13% and 29% to 6.7% and 18.3%, respectively. Composite milk samples from infected cows were examined for bacteriological isolation of S. aureus and E. coli. S. aureus and E. coli mastitis were determined in percentages of 25% and 30.9%, respectively. Following immunization, S. aureus and E. coli mastitis were decreased to 10% and 23.3%, respectively. The SCC on milk samples from animals with chronic infection significantly decreased after vaccination. Furthermore, a reduction in bulk milk tank SSC (BTSSC) was detected in the herd during the study. The application of vaccination has a greater impact on reducing the costs utilized for the treatment of mastitis in the herd. These findings indicate that the Lysigin vaccine has a protective effect against S. aureus mastitis and can be utilized as an additional approach for the management of mastitis.