Bovine mastitis is an infectious disease that impacts milk production, leads to economic losses and public health problems. It can present in subclinical and clinical forms, with subclinical being the most common. Currently, there is concern about the health of dairy cattle and alternatives are being sought for the treatment of bacterial infections, as those available may have low efficacy, promote antimicrobial resistance and/or have toxic effects. From a One Health perspective, multiple sectors must work together to control the rise in antimicrobial resistance. Regarding animal production, this implies changes in some traditional agricultural practices (WHO, 2022; OIE, 2022). According to Rabello et al. (2020), resistance to antimicrobials for Staphylococcus aureus isolated from bovine mastitis has recently increased compared to studies published in previous periods, in Brazil. In this context, homeopathy can represent an important therapy. In our study, two dairy herds in the state of Rio de Janeiro were evaluated, regarding the presence of mastitis, in two subsequent periods: 1- Control Stage (CS): using antibiotic therapy, and 2- Experimental Stage (ES): homeopathic treatment (Nosode 30CH). The CS took place from February to April 2022 and the ES from May to July 2022. For the analysis of the treatments, the animals were evaluated with the California Mastitis Test (CMT) and the milk from the positive mammary quarters, that presented mastitis, were collected and analyzed in the laboratory for bacterial isolation and identification. During the CS, 7 CMT were performed, and the same number in the ES. The occurrence of subclinical mastitis in the CS in 1681 analyzed quarters was 36.4% (n= 608), while in the ES, in 1290 analyzed quarters, subclinical mastitis was 26.5% (n= 335). There was a reduction (p<0.0001) in the occurrence of subclinical mastitis after homeopathic treatment. In both stages Staphylococcus spp. was the most prevalent microorganism.