A power-driven neck clamping mechanism for physical traction therapy includes a rail platform disposed on a base and a head rest member disposed on the rail platform. A clamping mechanism for retaining a user's neck includes a power-driven drive device, a transmission member, and two displacement members. The power-driven drive device is connected with the transmission member. The displacement members are movably disposed on the transmission member. The displacement members are disposed at two sides of the neck rest portion. The power-driven drive device drives the transmission member to actuate. The displacement members are controlled by the transmission member to displace. The displacement members can be moved to approach the user's neck to clamp and retain the neck, or the displacement members can be moved away from the user's neck to release the neck. The user can control the force to clamp the neck conveniently and finely.
