Ascochyta blight, which is caused by the fungus Ascochyta fabae f. Sp. Lentis, is considered as a very important fungal disease that infects lentils and cause it damage. The experiment was conducted in ICARDA research station for agricultural experiments in the orchard area Basha, Jableh, Lattakia in four varieties of lentils that are grown in different parts of Syria, and these varieties are: Idleb 2, Idleb 3, Idleb 4, and municipal red. Artificial infection was performed using a local isolation of the fungus Ascochyta lentis with an average of three times and ten days between each infection and the other. The infectious vaccine adopted a concentration of 105 Båge / ml.