Abstract: The aim of this experiment was to examine the effects of the different development stage of cotyledon, BA and NAA concentration, cultivar and culture condition on adventitious shoot regeneration from the immature cotyledon explants of the sweet cherry (Prunus avium L.). The results showed that MS culture medium with BA 2.0 mg·L^-1＋NAA 0.2 mg·L^-1 was the optimal for the adventitious shoot regeneration in the cultivar'Napoleon'and the optimal size of the immature cotyledon was PF (cotyledon length / embryo length×100) = 50-80 and the regeneration rate reached to 79.2%. Dark culture for 2 weeks prior to light culture was helpful to adventitious shoot regeneration. Shoot regeneration rate also reached to 72.2% in'Rainier', 61.1% in'Van'and 33.3% in'Lapins'. Adventitious shoots were mainly regenerated at proximal cutting region of cotyledon adaxial surface.

Key words: cherry, sweet cherry, immature cotyledon, regeneration, adventitious shoot