A virtual image display device for presenting a virtual image to a user via a virtual image presentation plate (22, 62), comprising: a display unit that generates an image display light by modulating an illumination light; and a projection optical system that projects the image display light toward the virtual image presentation plate (22, 62), wherein the projection optical system includes a main concave mirror that reflects the image display light toward the virtual image presentation plate (22, 62) and an auxiliary concave mirror that reflects the image display light toward the main concave mirror, and defining a plane along both a direction of incidence and a direction of output of the image display light on the virtual image presentation plate (22, 62) as a reference plane, the main concave mirror is provided in an orientation that causes the image display light to be incident on the main concave mirror in a direction along the reference plane, and the auxiliary concave mirror is provided in an orientation that causes the image display light to be incident on the auxiliary concave mirror in a direction intersecting the reference plane, characterized in that the image display light includes a first display light reflected by a first principal surface of the virtual image presentation plate (22, 62) and traveling toward the user and a second display light refracted by the first principal surface, reflected by a second principal surface of the virtual image presentation plate opposite to the first principal surface, refracted by the first principal surface, and traveling toward the user, in a composite optical system formed by the virtual image presentation plate and the projection optical system, the projection optical system is configured such that a second focal distance of the composite optical system on a second light path on which the second display light travels is shorter than a first focal distance of the composite optical system on a first light path on which the first display light travels, and the display unit is positioned between a first focal point and a second focal point of the composite optical system. a display unit that generates an image display light by modulating an illumination light; and a projection optical system that projects the image display light toward the virtual image presentation plate (22, 62), wherein the projection optical system includes a main concave mirror that reflects the image display light toward the virtual image presentation plate (22, 62) and an auxiliary concave mirror that reflects the image display light toward the main concave mirror, and defining a plane along both a direction of incidence and a direction of output of the image display light on the virtual image presentation plate (22, 62) as a reference plane, the main concave mirror is provided in an orientation that causes the image display light to be incident on the main concave mirror in a direction along the reference plane, and the auxiliary concave mirror is provided in an orientation that causes the image display light to be incident on the auxiliary concave mirror in a direction intersecting the reference plane, characterized in that the image display light includes a first display light reflected by a first principal surface of the virtual image presentation plate (22, 62) and traveling toward the user and a second display light refracted by the first principal surface, reflected by a second principal surface of the virtual image presentation plate opposite to the first principal surface, refracted by the first principal surface, and traveling toward the user, in a composite optical system formed by the virtual image presentation plate and the projection optical system, the projection optical system is configured such that a second focal distance of the composite optical system on a second light path on which the second display light travels is shorter than a first focal distance of the composite optical system on a first light path on which the first display light travels, and the display unit is positioned between a first focal point and a second focal point of the composite optical system.