A cyclopropene-ring-containing fatty acid ester, methyl (R)-2-hydroxysterculate, was isolated from Hibiscus rosa-sinensis along with methyl sterculate and malvalate. The stereochemistry of the asymmetric carbon at C-2 was determined as R by applying a dibenzoate chirality method, and a mild air oxidation afforded two conjugated enone isomers accompanying a ring opening.