Abstract: The key technology of Oncidium's industrial propagation were studied by in situ investigating the effects of the key factors such as minimal medium(improved MS,improved KC,V&W and self-prepared ZW series,etc.),phytohormone(6-BA,NAA,IBA,KT),additive(vitamin C,peptone,mashed banana,active carbon,sugar,etc.),on the mass breeding in every stage during Oncidium's industrial propagation.The results revealed that:(1)The protocorm like body(PLB) could be induce and increase as long as the concentration of 6-BA between 0.1～2 mg·L-1 and NAA 0.1～1.0 mg·L-1.At the revulsive initial stage a concentration of 6-BA 2 mg·L-1 and with NAA 0.2 mg·L-1 was helpful to increase the propagation basic number of protocorm like body.The multiply and differentiation of PLB could take place as long as 6-BA 0.05～0.1 mg·L-1 or addition of NAA 0.1 mg·L-1.The root emerging could be accelerated and the roots become stronger cooperation of addition of low concentration 6-BA(0.0～10.1 mg·L-1) together with NAA or IBA(0.1 mg·L-1).(2)The low concentration of auxin(0.01～0.1 mg·L-1) and the sort of low concentration of mineral medium(such as V&W,KC,etc.) seemed to benefit the decrease of the malformation during PLB differentiation and seedling growth.(3)In order to reduce the explant browning addition of active carbon 1 000 mg·L-1 and vitamin C 30 mg·L-1 was necessary.Adding peptone 5001 000 mg·L-1 or drawn substance of yeast seemed to promote the induction of PLB.Mashed banana 100 g·L-1 might benefit the PLB differentiation and improve the quality of test-tube plantlet.(4)Minimal mediums had notable effects on every stage of Oncidium tissue culture.The self-prepared ZW mediums with middle concentration of salt were more suitable to Oncidium propagation by tissue culture.(5)Oncidium was autotrophic without sugar in the medium.