An automatic two-gear transformer for a pure electric automobile comprises an input shaft, a first middle shaft, a second middle shaft, a third middle shaft, a first cylindrical gear pair, a second cylindrical gear pair, a third cylindrical gear pair, a first torque transmission device, a second torque transmission device and a differential assembly; rotation center lines of the input shaft, the third middle shaft and the differential assembly are mutually parallel. According to the automatic two-gear transformer for the pure electric automobile, automatic two-gear speed change is adopted, the transmission ratio range is expanded, the performance requirement on a drive motor can be reduced greatly, an efficient and light drive motor is allowed to be used, and the total size, the total mass and the total cost of an electric drive system of the pure electric automobile are further reduced.