Abstract: In the paper the relationship between graft effect and external morphology, growth phase, anatomical structure and nutrient composition of tender scions of Masson Pine have been studied systematically. The results showed that if tender twig was used as scion and the needle was covered with sheath or needle just appeared, the scion was delicate and produced rich callus easily. Moreover, water and nutrient composition content of tender scion was higher and organic carbon content was smaller, which was favourable to the healing between scion and stock and the increase of survival rate of grafting. Because tender scion was at primary growth phase, the ability of cell division and differentitation was stronger, and there was larger growth increment after grafting. The above result was good proof for establishing seed orchard of Masson Pine using tender twig as scion.