The invention discloses a method for treating isobutyrate-containing wastewater by alcohol etherification, comprising the following steps: 1), acidifying isobutyrate-containing wastewater with concentrated sulfuric acid, adding alcohol, subjecting a reaction system to etherification under reflux condition so as to generate isobutyrate, and stopping reacting until no water is generated in the reaction system; 2), cooling reaction liquid obtained in step 1) to room temperature, re-adding water separated from the reaction system and obtained in step 1), into the cooled reaction liquid, and stirring and standing to obtain oil phase and water phase; subjecting the water phase to solid-liquid separation to obtain low-COD wastewater and sulfate; 3), rectifying the oil phase obtained in step 2); collecting an alcohol fraction and an isobutyrate fraction. The wastewater treated by the method has low COD value.