Abstract: Carya cathayensis ,native to China,is an important species for dried nuts and oil,with high nutritional and economic values.At the present it is mainly propagated by seed,with a long juvenile stage and late fruiting stage,so it needs a long time before getting profit.For decades,researchers have carried out a series of studies on the propagation techniques of this species,especially the grafting techniques,but no great achievements have been made till now.The production of Carya cathayensis on large scale is severely restricted by the very low grafting survival rate.For this reason,plant growth regulators had been taken in order to improve the grafting survival.Using three plant growth regulators(IAA?6 BA and GA 1,3 ),three concentration to deal with three types of scion(seedling stem,nourishing shoots,fruit productive branches)for grafting.Field test of direct cross(L 27 3 3)showed that IAA had a significant function.In the graft of seedling stem as scion,the F value was 2.91,which is over F 0.10 .Meanwhile,the F value of nourishing shoots and fruit productive branches as scions were 3.94,3.49 respectively,which were all over F 0.10 .Gibberellin mixed with IAA showed that they promoted each other on fruit productive branches grafting.6 BA had no effect on its grafting.So IAA was the most important one of the three regulators in the grafting.However,the effect of growth regulators changed when it was used in different time.The effective grafting date was before the leaflet developed.