There is provided an FGF2 substitute-containing medicinal composition which comprises, as an active ingredient, a chimeric protein comprising the amino acid sequence of an FGF1 protein in which a partial sequence including a sequence of at least positions 62-83 within a sequence of positions 41-83 is substituted with a partial sequence at the corresponding positions in the amino acid sequence of an FGF2 protein; and the remaining region is formed of the amino acid sequence of FGF1. In particular, this medicinal composition is used for wound healing and for the prevention and treatment of radiation-induced damage, and it exhibits a pharmacological action superior to that of an FGF2 medicinal composition, and further, it can be easily formulated into a preparation.