To provide a method for industrially and advantageously producing an olefin oxide in which oxidative reaction can be advanced in high reactivity and good selectivity without causing deactivation of a catalyst even in low-oxygen partial pressure.

The method for producing acetal and/or vinyl ether comprises reacting an ethylenic double bond of a compound having the ethylenic double bond with oxygen and an alcohol in the presence of a catalyst containing palladium, iron and copper. In the production method, the molar ratio of total of iron and copper to palladium is kept to ≥100.