1. A head-mounted display device with which a user can visually recognize a virtual image and an outside scene simultaneously, the head-mounted display device comprising: an image pickup unit configured to pick up an image of the outside scene and acquire an outside scene image; an augmented-reality processing unit configured to analyze the acquired outside scene image and generate additional image data for augmented reality according to a result of the analysis; a display element configured to generate image light using the generated additional image data; and a light guide unit configured to form a virtual image before eyes of the user using the generated image light, wherein the augmented-reality processing unit acquires an overlapping region where a display region for the virtual image and an image pickup region of the image pickup unit overlap in the outside scene image and generates the additional image data using the overlapping region.