Abstract: Growth and physiological implications on Cymbidium plant under the increased CO2 concentration were studied.The results show that the increased CO2 promoted plant growth and development.Increased CO2 significantly promoted the growth of flower buds,but not the flowering rate.CO2 concentration made the flowering start early,but no significant effect on the length of flowering period.Elevated CO2 also resulted in reduced stomatal conductance(SC) and transpiration rates(TR),as well as,an increased net photosynthetic rate.