A stereoscopic image display device for displaying a three dimensional (3D) stereoscopic image in real-time by using a 3D graphic contained within a 2D image. The stereoscopic image display device includes a controller, a 3D graphic processor, a driver, and a display unit. The controller receives 3D graphic data and a synchronization signal, and outputs a control signal and the 3D graphic data. The 3D graphic processor generates a plurality of stereoscopic matrices used to generate 3D stereoscopic image data for a plurality of viewing points according to the control signal, and transforms the 3D graphic data into 3D stereoscopic image data using the plurality of stereoscopic matrices. The driver generates a driving signal based on the image data output from the 3D graphic processor and the output control signal. The display unit displays an image corresponding to the image data according to the driving signal.