It is intended to contribute to the solution of environmental problems caused by destroying the ozone layer and serious problems concerning the food resources in the 21st century by isolating a photoreactivating enzyme from an ultraviolet light-tolerant rice plant, thus acquiring information on the photoreactivation mechanism of the plant which still remains unknown mostly, and constructing an ultraviolet light-tolerant plant with the use of a cloned gene. Genes encoding a photoreactivating enzyme originating in rice plant, in particular, a gene encoding a protein as specified in the following (a) or (b): (a) a protein comprising the amino acid sequence represented by SEQ ID NO:1; and (b) a protein comprising an amino acid sequence derived from the amino acid sequence (a) by deletion, substitution or addition of one to several amino acids and having a photoreactivating enzyme activity.