The invention discloses a rotatable sightseeing platform based on a large transmission tower. The sightseeing platform includes a spherical platform, first circular orbits, second circular orbits anda power output system installed in the spherical platform. The first and second circular orbits are fixedly mounted on a tower body, and first and second rail wheels are fixedly mounted on the spherical platform. The spherical platform rotates along the first circular orbits through the first rail wheels and rotates along the second circular orbits through the second rail wheels. The tower body isprovided with a rotating device, the spherical platform is provided with a plurality of hanging holes, and slings are connected between the rotating device and the hanging holes. The power output system is connected with the first and second rail wheels separately to drive the first rail wheels to move along the first circular orbits and drive the second rail wheels to move along the second circular orbits. The sightseeing platform is constructed on the large transmission tower for sightseeing, rotates at 360 degrees along the orbits through the power output system and under the support of the tower body, and provides tourists with 360-degree mobile viewing.