Bacteriocins are extra-cellular released peptides or protein with a bactericidal or bacteriostatic mode of action against many Gram positive and Gram negative bacteria. Bacteriocins produced by lactic acid bacteria (LAB) have received particular attention in recent years due to their potential application in the food industry as natural preservatives. In this study, bacteriocin was extracted from Lactobacillus acidophilus to determine its inhibitory effect against Bacillus subtilis, Staph.aureus (Gram-positive bacteria) and E.coli (Gram-negative bacterium). The largest inhibition zone was obtained against Bacillus subtilis followed by Staph.aureus while the smallest inhibition zone was obtained against E.coli. The results revealed that the activity of bactericin extract was gradually decreased during storage at 370C until 60 days and it was completely lost up to 90 days of storage. It was stable at 40C until 30 days then its activity was gradually decreased till 90 days of storage. While, the storage of extracted bacteriocin at -200C persisted its activity for 90 days. Also, the current study concluded that freezing temperature was the most appropriate technique for preservation of bacteriocin.