The present disclosure discloses three-dimensional glasses and a three-dimensional display system, which provide a wearer with a better three-dimensional visual effect and reduce dizziness and fatigue of the wearer. The three-dimensional glasses include a frame including two lens frames, each lens frame having an engagement part; two lenses rotationally assembled in the engagement parts of the two lens frames, respectively; and at least one counterweight member fixed to a periphery of each of the lenses and rotating the lens to an equilibrium position. When the two lenses are at the equilibrium positions, a transmission axis of one of the two lenses is parallel to a polarization axis of a left eye image of a three-dimensional display apparatus and a transmission axis of the other one of the two lenses is parallel to a polarization axis of a right eye image of the three-dimensional display apparatus.