Diseased tomato samples showed typical symptoms of the early blight disease were collected from four Egyptian governorates , i.e. Sharkia, Kalubia, Gharbia and Ismailia. All Alternaria solani isolates affect Peto 86 tomato cultivar. Ismailia was the most aggressive isolet. Three Bacillus subtilis isolets (were isolated from planosphere of tomato leaves) and tow Trichodermaviride isolates (were isolated from rhizosphere) inhibited A. solani growth with different levels. The most aggressive B. subtilisisolate was chosen as a tool to induce disease resistance for tomato seedlings. The application of Bacillus subtilis on tomato seeds achieved a profuse proliferation of endophytically colonized seedlings, tomato plants were then challenged with A. solani suspension. The av. hight of endophytically colonized plants increased from 38 cm for the check plants to 57 cm for the treated ones. After 45 days keeping under greenhouse conditions, the endophytically colonized and challenged tomato plants exhibited a significant reduction in early blight severity (7% compared with 19 % for check plants). The endophytic bacteria was recovered from treated tomato seedlings, indicating that the endophytic B. subtilis has the potential to move systemically throughout the plant tissues .