A three-dimensional-image display device includes a display unit, a variable focus lens unit, and a controller. The display unit sequentially displays a first image displayed by a first image signal and a second image displayed by a second image signal, and that projects a display light of the first image and a display light of the second image. The variable focus lens unit switches the focal lengths for the display lights to respectively form, as virtual images, the first image and the second image on a first display surface and a second display surface. The controller controls, on the basis of a start timing at which writing, of an image signal of a different image, to pixels of the display unit starts, a projecting timing at which the display unit projects the display light of the first image and the display light of the second image.