In this study, the growing ability of Lactococcus lactis ssp. lactis BZ and Enterococcus faecalis KP in different fat content milk at 30°C for 48 hours and the efficiency of their bacteriocins, lactococcin BZ and enterocin KP, against three types of cheese starter (Choozit MA 11LYO 50, Choozit MA 19LYO 50 and DI-Prox M265) in full fat milk were determined. The growth and bacteriocin production abilities of L. lactis ssp. lactis BZ and E. faecalis KP in milk were examined for 48 hours at 30°C. As a result of the study, it was determined that both bacteria grew better in milk with low fat content and produced more bacteriocin. It was found that lactococcin BZ (1600 AU/mL) and enterocin KP (1600 AU/mL) had an inhibitory effect against three different cheese starter cultures analyzed when used separately or in combination.