A wrinkle-improving agent that has an effect of improving wrinkles, that does not entail problems of safety or pain even when applied to the skin, and that contains a very safe substance as an active component. A discovery was made that N-benzoyl-β-alanine, other specific β-alanine derivatives, and salts thereof have a wrinkle-improving effect, whereby a wrinkle-improving agent containing as an active component one, two, or more types of compounds selected from the group composed of these specific β-alanine derivatives and the salts thereof was developed.