Furfural /ˈfɜːrfjᵿræl/ is an organic compound derived from a variety of agricultural byproducts, including corncobs, oat, wheat bran, and sawdust. The name furfural comes from the Latin word furfur, meaning bran, referring to its usual source.

Furfural is a heterocyclic aldehyde, with the ring structure shown at right. Its chemical formula is OC₄H₃CHO. It is a colorless oily liquid with the odor of almonds, which quickly darkens when exposed to air.