The invention discloses an electric-starting and damping-adjustable transmission system torsion damping device. The electric-starting and damping-adjustable transmission system torsion damping devicecomprises an electric starting device, a damping adjusting device and a dual-mass flywheel assembly. The starting torque can be controlled by adjusting the current, and the damping can be adjusted byadjusting the friction force between two masses. According to the electric-starting and damping-adjustable transmission system torsion damping device, the damping between dual-mass damping flywheels can be adjusted, so that torsional vibration of a transmission system is effectively reduced; and a starting mechanism and the flywheels are integrated, so that the starting mechanism of an internal combustion engine is simplified.