To provide a stereoscopic image display device simplifying a structure and enlarging possible lateral range which enables stereoscopic display at a relatively low cost.

This stereoscopic image display device is provided with a liquid crystal panel 1 for display constituting a display screen by a pixel group for a left eye and the pixel group for a right eye, a light source 2 provided on the light incident side of the liquid crystal panel for the display and an image separation means 3 arranged on the light emission side of the liquid crystal panel 1 for the display and constituting a barrier part generating a binocular parallax effect. The image separation means 3 is constituted of a liquid crystal panel part 30 for polarizing the polarization axis of image light from the liquid crystal panel 1 for the display and a polarization part 34 formed having the pattern of the different axial directions of polarized light alternately transmitted so as to separate left and right image light from the liquid crystal panel. The drive of the liquid crystal panel part 30 is controlled by the position of an observer 5 and the position of the light transmitted through the polarization part is switched.