A head-up display includes a display unit displaying images in a display region defined on a vehicle windshield, a vehicle information acquisition unit acquiring vehicle information, a forward view information acquisition unit acquiring forward view information, a display object detection unit detecting a display object for which guidance information is required to be displayed in the display region, a display control unit, and a display form setting unit. The display control unit generates a guidance image indicating the guidance information of the detected display object and displays the generated guidance image over the display object in superimposed manner on the windshield. The display form setting unit calculates an annoyance value indicative of an annoyance level felt by a vehicle occupant when displaying the guidance image in superimposed manner, and sets a display form of the guidance image so that the calculated annoyance value is within a predetermined appropriate range.