Cholest-4-en-3-one 26-monooxygenase (, CYP125, CYP125A1, cholest-4-en-3-one 27-monooxygenase) is an enzyme with systematic name cholest-4-en-3-one,NADH:oxygen oxidoreductase (26-hydroxylating). This enzyme catalyses the following chemical reaction
Cholest-4-en-3-one 26-monooxygenase is a heme thiolate (P450) enzyme.