a power transmission device is embedded in an electric vehicle equipped with an electric motor and a transmission . the transmission includes a first reduction mechanism and a second reduction mechanism . the power transmission device also includes a spline hub coupled to an output side of the first reduction mechanism , a clutch plate coupled to an input side of the second reduction mechanism , and a coupling portion . the coupling portion is disposed between the spline hub and the clutch plate , and includes a damper mechanism configured to absorb a vibration from the spline hub and transmit a torque to the clutch plate , and a torque limiter configured to transmit the torque and to limit transmission of the torque when the torque is greater than or equal to a predetermined magnitude .