Shoot-tips from Cymbidium hybridum were used as the explants to investigate the effects of 6-BA and NAA in different concentration proportions on PLB(protocorm-like body) induction,propagation and differentiation.The results show that the survival rate of shoot-tips is 93.3% in the concentration proportion of 1.0 mg/L 6-BA + 0.5 mg/L NAA,the induction rate of PLB is 85.8% in the concentration proportion of 0.8 mg/L 6-BA + 0.4 mg/L NAA,the propagation rate of PLB is 4.59 in the concentration proportion of 1....