Abstract: Embodiments of this application disclose a data processing method and a related device. One example method includes: A control device receives a first data transmission request sent by a diagnostic device, where the first data transmission request is used to request the control device to receive an upgrade file, the first data transmission request carries a first memory address corresponding to the upgrade file, and the upgrade file is used to upgrade the control device. The control device obtains a first file path corresponding to the first memory address, receives the upgrade file sent by the diagnostic device, and stores the upgrade file into a file to which the first file path points.