In a back-projection image display device, image light outputted from a projection device is reflected by a reflection mirror held by a base frame and projected onto the back of a screen, to display an image on the screen. An image distortion correcting mechanism includes adjustment mechanisms that deform the reflection mirror, drive units that generate driving force necessary for the deformation of the reflection mirror by the adjustment mechanisms, and a control substrate that supplies power to the drive units. The control substrate supplies power to the drive units in response to a control signal supplied from a remote control unit. This allows pin distortion and barrel distortion, as well as trapezial distortion to be corrected by remote control in the back-projection image display device.