【Objective】Transformation regeneration system of epicotyls derived from Citrus paradisi Macf. cv Duncan seedling were established in order to provide useful reference for its gene transformation. 【Method】Epicotyls of seedling were used as explants to investigate the influence factors on induction and differentiation of adventitious buds， rooting of plantlets， and genetic transformation. 【Result】The induction rate of adventitious buds derived from epicotyles were ranged from 72.7% to 81.6% in media with 0.50-1.00 mg/L TDZ. Comparing three types of growth regulators， the higher rooting rate （81.3%） were observed in 1/2MT medium with 1.0 mg/L of ABT 6 rooting powder. Among different antibiotics， timentin showed better sterilizing effects than cefotaxime sodium and ceftriaxone sodium on agrobacterium-mediated transformation plantlets culture. Timentin had no inhibition on buds induction of explants. During initial transformation stage of buds， 5-7 days of darkness culture was beneficial to induce Kan anti-buds. Among 7 transgenic plantlets， 6 plantlets showed positive in PCR detection. 【Conclusion】Regeneration system of Citrus paradisi Macf. cv Duncan ecopityls was established and provided base on its genetic transformation.