Abstract: Effective light intensity at underwater is the main limiting factor which affects the ecological restoration of submerged plant communities. We used artificial constructing underwater illumination compensation for Vallisneria natans L. in ecological restoration in turbid water(90 NTU). We investigated the effect of different levels of the underwater illumination compensation on V. natans seedling survival, leaf morphological and physiological changes in metabolism mechanisms. The results showed that the high level of underwater illumination compensation increased the survival rate of V. natans seedlings, the total biomass of seedlings, the average biomass per plant and the number of clones(significantly increased 25%, 220%, 150% and 160% compared with the control group, respectively). Through the underwater illumination compensation, V. natans increased its seedling leaf number, leaf length and width, and this trend was enhanced by increasing illumination intensity(high level of underwater illumination compensation group significantly increased 130%, 100% and 30% compared with the control treatment, respectively). Due to water turbidity, the control group decreased chlorophyll content in leaves and chl a/b ratio. Through the underwater illumination compensation, SOD and POD activities of seedlings were also increased, indicating that the underwater illumination compensation was unable to increase seedling leaves of reactive oxygen. In summary, the underwater illumination compensation could promote the V. natans seedling survival, growth and physiological indexes. Therefore, the underwater illumination compensation system should be an effective submerged vegetation restoration method.