An electronic control device for a vehicle according to the present invention includes an action prediction unit that predicts the action of an object around the vehicle on the basis of external information acquired from external information detection units that detect external information of the vehicle, and a determination unit for a detection unit that determines whether an abnormality has occurred in the external information detection unit by comparing external information acquired from the external information detection unit at the time corresponding to a prediction result of the action prediction unit to the prediction result of the action prediction unit.