The invention provides a method for manufacturing a USB tax control data backup device for a tax control cash register. The method is characterized in that a USB memory is taken as a data storage carrier. The method comprises the following steps: the tax control cash register encrypts data through a USB interface; the tax control data, after being identified by legitimate equipment, is backed up onto the USB memory to form the USB tax control data backup device; and the data can be examined and maintained through special receipt data maintenance software loaded on a computer. The invention ischaracterized in that the tax control cash register system inputs receipt detail data and receipt usage data into the USB tax control data backup device provided by the invention, then the data is input by the USB tax control data backup device into the computer, the input receipt data can be referred to through the special receipt data maintenance software, and the data for inquiry is output as an Excel-format document or a Txt-format document as designated according to service requirements, so that management and application of the receipt data by a user can be facilitated.