Three strains of   lactic acid bacteria were used as adjunct bacteria with the normal starter of Ras cheese. The strains were grown in Ras cheese slurry for 15 days. The influence of each strain was assessed on the basis of the biomass growth, rate of autolysis, rate of  both proteolysis and lipolysis. The results indicated that the addition of Lactococcus. Lactis sub.lactis gave an excessive stimulation effect on biomass formation and autolysis for either streptococci or lactobacilli. The biochemical changes in the slurry due to the type of the adjunct bacteria revealed to the disadvantages of using Lactobacillus casei as it showed lower pH value, higher lipolysis and lower proteolytic activity. This effect might be related to the low activity for biomass formation as well as to the lower lysis ability.   The results revealed to the superiority of Lactococcus lactis sub. lactis for biomass production, autolysis and proteolysis.  On the other hand, the strain of Streptococcus thermophilus   showed an advantage effect on growth and lysis of Streptococci only.