The emergence of antimicrobial resistance and the emergence of novel pathogens pose a serious threat to public health and animals around the world. Peppermint (Mentha piperita) has a variety of therapeutic features, one of which is an antibacterial property that can be helpful in preventing infections in wildlife. This property can be found in the extracts of both the stem and the leaf of the plant. In the current investigation, an extract of Mentha piperita (M. piperita) or clocally named as peppermint stem and leaf was produced in methanol at a concentration of 70 percent to test its effectiveness as an antibacterial agent against three Gram-negative bacteria. i.e. Escherichia coli (E. coli), Salmonella Typhimurium (S. Typhimurium) and Pseudomonas aeruginosa (P. aeruginosa) and against one Gram-positive Bacteria Staphylococcus aureus (S. aureus). Fresh feces and skin swab samples were taken from wild sheep in the Wildlife Park Gatwala, Faisalabad, during February 2022. The isolated strains of bacteria were identified and confirmed microbiologically. Peppermint (stem and leaf) extracts prepared with methanol were examined for their efficacy against the identified pathogens. The extracts demonstrated higher inhibitory zones (leaf: 17.5mm, stem:16mm) against S. aureus. S. Typhimurium, P. aeruginosa and E. coli. The leaf extract showed zones of inhibition of 16.5, 16, 15.5 and 13mm while stem extract produced zones of inhibition of 15.5, 14, 16.5, 15mm against S. aureus. S. Typhimurium, P. aeruginosa and E. coli, respectively. Furthermore, the broth dilution method revealed that the MIC of peppermint (stem and leaf) was 0.4mg/ml against all tested bacterial strains. Altogether, these findings indicate that peppermint extracts may be useful in combating common bacterial infections of wild sheep.