A virtual image display device includes a virtual image position selector, a vision measurement interface, a display information acquirer, a display image generator, and a projection processor. The virtual image position selector selects either a first virtual image position or a second virtual image position as a display position of the virtual image. The vision measurement interface measures a vision of a user based on a user's response to a vision measurement image projected as a virtual image at the display position. The display information acquirer acquires information to be shown. The display image generator generates a display image showing an image corresponding to the information acquired by the display information acquirer in a size determined by the vision acquired by the vision measurement interface. The projection processor performs a projection process of projecting the display image generated by the display image generator as a virtual image.