In enzymology, a retinal oxidase (EC 1.2.3.11) is an enzyme that catalyzes the chemical reaction

retinal + O₂ + H₂O ${\displaystyle \rightleftharpoons }$ retinoic acid + H₂O₂

The 3 substrates of this enzyme are retinal, O₂, and H₂O, whereas its two products are retinoic acid and H₂O₂.

This enzyme belongs to the family of oxidoreductases, specifically those acting on the aldehyde or oxo group of donor with oxygen as acceptor. The systematic name of this enzyme class is retinal:oxygen oxidoreductase. This enzyme is also called retinene oxidase. This enzyme participates in retinol metabolism.