The invention relates to the technology of electric automobiles, in particular to a drive device of an electric automobile. The drive device of the electric automobile comprises a battery pack, a motor drive circuit and an electric motor, and is characterized by further comprising a Z source converter, wherein the Z source converter is connected with the battery pack and the motor drive circuit respectively; and the motor drive circuit is connected with the electric motor. The drive device of the electric automobile has the benefits as follows: when motor drive adopts full bridge drive, a direct connection state can be allowed; high-magnification buck-boost of a low voltage battery pack can be well realized, and the magnification adjustment range is wide; and when the number of batteries is small, a whole system can be driven, motors with different nominal voltage can be driven in the same battery management system in a wider range, and modular design of the battery management system is facilitated. The drive device of the electric automobile is particularly suitable for the electric automobiles.