A data refreshing method and a data refreshing device for after an ECU flush fails, which are applicable to the technical field of automotive electronics. The method comprises: establishing a communication connection between a data refreshing device and an ECU of a user vehicle (S101); determining the configuration information concerning a user vehicle (S102); acquiring an ECU data file matching the configuration information concerning the vehicle (S103); and refreshing the ECU data file of the user vehicle by means of the established communication connection (S104). The present invention enables direct refreshing of the ECU of the vehicle without the need to go to a special vehicle model after-sale service mechanism for refreshing, being simple and convenient in operation, and low in cost.
