Part attachment work support system and part attachment method

This system is provided with: an imaging means for imaging a work space, together with a workpiece to which parts are to be attached, in the direction of the line of sight of an operator at the viewpoint position of the operator; a position and orientation information acquisition means for acquiring position and orientation information representing the relative position and orientation relationship of the viewpoint of the operator and the workpiece in the work space; a virtual image generation means for generating, on the basis of the position and orientation information, a three-dimensional virtual image representing the viewpoint position and attached parts in the direction of the line of sight; an image synthesis means for generating a synthesized image formed by superimposing the virtual image on an actual image of the work space; and a display means for displaying the synthesized image. This system enables mixed reality technology to be utilized to greatly improve the efficiency of part attachment work.