All the bacterial disorders are treated with antibiotics. Drug resistance and recurrence of infection are still a major problem (Jojart 1978, Reid 2001). Synergitic effect of bacteriocin obtained from fermented milk against pathogens is the criteria of the study. In the fermentation of goat and cow milk by Lactobacillus and Streptococci sp the pH decreased rapidly from 6.2 to 3.6 in 25 hours. The pathogens E.coli, Staphylococcus sp and Pseudomonas sp were highly inhibited by fermented goat milk rather than the fermented cow milk. The pathogens E.coli, Staphylococcus sp and Pseudomonas sp were highly inhibited by fermented goat milk rather than the fermented cow milk. The partially purified bacteriocin expressed very high inhibitory activity towards E .coli (30 mm and 28 mm). It exhibited moderate activity towards Staphylococcus sp and Pseudomonas sp. One single protein band was obtained in the gel, indicating that bacteriocin was properly purified. The molecular weight of the bacteriocin was determined as 45,000 Da.