Abstract: The filling duration of 1 h·d^-1（20:00—21:00）,4 h·d^-1（20:00—24:00）,7 h·d^-1（20:00—03:00） were studied by using LED full-spectrum light at night to fill light of water cabbage, and light intensity 3 000,7 000,11 000 lx on the growth and yield of water cabbage, in order to provide reference for plants to fill light at night.The results showed that the treatments under supplemental light conditions were better than the control.All growth indexes of water cabbage increased with the increasing of light intensity under the supplemental light duration of 1 h·d^-1.Under 4 h·d^-1 supplemental light duration, plant height, stem diameter, yield and dry weight of water cabbage were positively correlated with light intensity, while fresh weight, number of leaves and leaf area showed single peak at 7 000 lx light intensity.Under the photoperiod of 7 h·d^-1,the indices firstly increased and then decreased with the increase of light intensity.The growth indexes of water cabbage increased with the increasing of the light intensity of 3 000 lx and 7 000 lx.At 11 000 lx light intensity, plant height, stem diameter and yield reached the maximum values at 4 h·d^-1,while fresh weight, dry weight, leaf area and leaf area reached the maximum values at 7 h·d^-1.In conclusion, the combined treatment of 7 h·d^-1 and 7 000 lx at night was more suitable for the growth of water cabbage.