Rice was grown in nutrient solutions of different Se concentrations in an experiment. Physiological and biochemical characters of Se on rice were studied after treatment with ultraviolet ray. The results showed that in proper concentration range(<0.10 mg·L -1 ),the MDA content, the O - 2 production rate and the free radical production descended. The injuries of cell ultra structure were reduced in UV adversity. The vigor of mitochondrial was increased. The electron transfer rate of the chloroplast was raised. Its effect on physiology and biochemistry of rice was reversed if the concentration was over a proper range.