The invention discloses a liquid-electric combination space thruster, which comprises a combustion chamber, a catalyst, an insulator, an anode, a nozzle, a permanent magnet ring and a power supply system. The catalyst particles are filled inside the combustion chamber; a circular through hole is opened between the two end faces of the insulator, and installed in the combustion chamber, located downstream of the catalyst (along the flow direction of the propellant, the same below); the geometric shape of the anode and the insulator The same, and installed in the combustion chamber, located downstream of the insulator; the nozzle is connected to the tail of the combustion chamber; the permanent magnet ring is nested at the outer tail of the combustion chamber; the positive pole of the power supply system is connected to the anode, and the negative pole is connected to the catalyst . The present invention integrates the liquid rocket engine and the plasma rocket engine into a liquid-electric combined space thruster, so that one engine has two working modes, and the aircraft uses the mode of burning propellant to work when performing low-orbit missions (the propulsion The chemical energy of the agent is converted into kinetic energy), and the aircraft uses plasma propulsion when performing high-orbit or deep-space exploration missions (converting the kinetic energy of the power supply into kinetic energy), so that one thruster can meet the needs of different missions of the aircraft, thereby reducing the total mass of the spacecraft.