This work was conducted at the experimental farm of the Horticultural Research Institute, Giza governorate during the two grovw'ng seasons (2002 and 2003). to study the effect of Kalamata top grafting on three olive rootstocks (koroneiki. Manzanillo and Picual cvs.) and to investigate the efficiency of foliar application of GA; with regard to dose and time of treatment on the grafted Kalamata plants - GA3 at (100. 200 8. 300 ppm) was applied at three dates (Mide May, June and July). Data revealed that. Kalamata scion cv. grafted on Manzanillo olive rootstock surpassed other rootstock cvs. in the scion growth and grafting survival percentage in both seasons. Whereas. Kalamata scion cv. grafted on Manzanillo olive rootstock sprayed with 300 GA3 three doses performed the highest significant values in the root length. root and shoot dry weight compred to other treatments during the two growing seasons. Whileas. Kalamata scion cv. grafted on Picual olive rootstock cv. sprayed with water one dose (mide May) performed the highest significant value in No. of roots in both seasons. Kalamata scion cv. grafted on Picual rootstocks and sprayed three closes with 300 ppm Gk gave the highest No. of leaves and leaf area during 2002 growing season. Meantime, Kalamata scion cv. grafted on Manzanillo and sprayed two closes with 200 ppm GA; gave the superior No. of leaves compared to the other values during the second one. Grafting Kalamata cv. on Koroneiki rootstock plants which sprayed two closes with 100 ppm GA: influenced significantly shoot/ root ratio compared to the other treatments in the interaction effect during the two growing seasons. Kalamata scion cv. grafted on Picual and Koroneiki rootstock plants sprayed one dose with 300 ppm GA; surpassed the other treatments in number of branches in the first and second ones, respectively. Kalamata scion cv. grafted on Koroneiki rootstock cv. sprayed with 300 ppm GAa one and three doses gave the highest graft length during 2002 and 2003 growing seasons. respectively. Kalamata scion cv. grafted on Picual rootstock cv. sprayed three doses with 200 ppm GA; gave the best graft thickness in both seasons. Complete healing was noticed in Kalamta scion cv. grafted on the three rootstock/scion of Koroneiki, Manzanillo and Picual cvs. without any gap or split. The recommended rootstocks for Kalamata grafting can be arranged in descending order as follow Manzanillo. Koroneiki and Picual rootstocks besides. spraying it with 300 ppm GA3 concentration. three doses during the two growing seasons.