3-nylpropionic acid is a monocarboxylic acid that is propionic acid substituted at position 3 by a nyl group. It has a role as an antifungal agent, a human metabolite and a plant metabolite. It is a monocarboxylic acid and a member of benzenes. It derives from a propionic acid. It is a conjugate acid of a 3-nylpropionate.