The invention discloses a three-axle hybrid power driving device and belongs to the field of driving of hybrid power automobiles. According to an electrombile double-motor four-gear transmission, an engine driving mechanism is additionally arranged on the basis of the electrombile double-motor four-gear transmission and is used for introducing power into an original double-motor four-gear transmission so as to form four pure electric gears and eight hybrid driving gears. According to the three-axle hybrid power driving device, the problem of poor power of hybrid power automobiles can be effectively solved; the output torque is continuous and the power is not interrupted in the processes of shifting gears and switching a pure electric mode and a hybrid driving mode; the problem of the power interruption is avoided; the comfortable level is improved; two hybrid driving gears can be added by additionally arranging a pair of pure electric gears in the original double-motor four-gear transmission, so that the high torque of low-speed driving and the power of high-speed driving can be better ensured.