Chitinolytic enzymes of B. licheniformis , which used as antifungal agent were studied, and the results revealed that the growth of B. licheniformis reached its maximum activity in the third day. Maximum enzyme activity was observed in the fifth day. Colloidal chitin + arabinose up to 1.5 + 0.1% were observed as a superior source for enzyme production. Yeast extract enhanced the enzyme biosynthesis. Enzyme production was strongly influenced by aeration. pH 8.0 and 45°C were appeared to be the optimal for chitinase production. Maximum specific activity, recovery and purification fold were found with the use of 60% saturation of ammonium sulphate, being 23.39 units/mg protein, 52.4% and 9.4 folds, respectively. 45°C and pH 7.5 were found as the optimum temperature and pH for enzyme activity. Enzyme was stable up to 60°C and lost 15% only from maximum activity at 70°C, indicating that this enzyme is a thermostable one. Enzyme activity apparently is rather stable with a broad pH ranging from 6.0 to 8.0. Thus, the enzyme has advantageous for use in biotechnology as antifungal agent. CaCl2, MgSO4, MnSO4 and FeSO4 stimulated the enzyme activity, while HgCl2 at 10 mM inhibited the enzyme activity. B. licheniformis chitinase succeeded to hydrolyze the three substances tested, which was found as lytic one and may be use as antifungal agent. The addition of B. licheniformis chitinase to the nutrient media of some parasitic fungi, inhibited its growth and its sporulation rate. Therefore, this enzyme may be play an important role in the defense against parasitic fungi on higher plants.