Objective To investigate the suitable light intensity of plant growth of Dendrobium Sw.through study on photosynthetic characteristics.Methods The photosynthesis curves of light intensity, chlorophyll fluorescence parameter of different light intensity and inductivity of non-photochemical quenching of chlorophyll fluorescence in 3.0?104 lx on three species of Dendrobium Sw.in Huoshan (D.huo- shanens, D.candium, and D.moniliforme) were determined.Results Three species of Dendrobium Sw.were shadow plants for their response on light intensity, light saturation point, light compensate point, net photosynthesis rate, and apparent quantum efficiency are lower during photosynthesis.The photoinhibitory effect was formed on Dendrobium Sw.leaf when they grew in more than 4.0?104 lx.Conclusion Although three species of Dendrobium Sw.in Huoshan grow in (0.2-2.0)?104 lx normally, they are suitable to grow in (2.5-3.0)?104 lx instead of growing more than 4.0?104 lx.