A three-dimensional display device is provided in the present disclosure. The three-dimensional display device includes an image displaying device, an optical control element, a direction sensor and a control unit. The optical control element is positioned on a surface of the image displaying device, the direction sensor measures and inclination angle of the display panel, and the control unit adjusts images displayed by the image displaying device according to the inclination angle. The three-dimensional display device of the present disclosure has the advantages of fast tracking speed, high tracking precision and low cost. A mobile terminal and a three-dimensional display tracking method are also provided in the present disclosure.