Magnetic planetary gear (MPG) and coaxial magnetic gear (CMG) were the two types of magnetic gears with different topologies and operating principle. By using quantitative design method and finiteelement method the torque performance of the MPG and the CMG, which with the same effective volume and the amount of permanent magnets, were compared. The results revealed that the MPG possess a higher torque density and lower torque ripple. Furthermore, considering the MPG had more flexible operation mode and could realize power split, which made MPG an interesting candidate in hybrid electric vehicles, a prototype of MPG was fabricated and tested. Both theoretical analysis and experimental results verified the effectiveness of this topology.