Abstract: The shoot tips about 1mm of grafted citrus tree underwent good differentiation on amodified MS medium supplied 6-BA(1.0 mg/L)and NAA(0.4 mg/L).The differentiation rate ofshoot tip varied with the different growing stages.The sproutings just affter the dormancy or atthe vigourous growth stages were most suitable to be the original explants for shoot tip culture.The differentiation rate of shoot tip may reach 78.4%-85.7%and grow well on above moified MS medium.The propagation rate also varied with the different varieties.Healthy plantletsmay be obtained from the continuously cultured buds growing on the modified MS medium.Soaking the base parts of newlydeveloped shoots with 100 mg·kg-1 IBA was favourable to root formation.Optimum concentration of hormone and sucrose,suitable pH in culture medium and sufficient illumination could effectively control the occurance of yellowing and transparent plantlets in the culture tubes.