A scanning-type display device includes: a light source which emits projection-display laser light; a condensing unit which condenses the laser light emitted from the light source; an optical scanning unit which uses the laser light passing through the condensing unit in scanning; and a light diffusion unit which includes a plurality of light diffusion channels arranged in two dimensions and diffuses the laser light scanned by the optical scanning unit. When a wavelength of the laser light is denoted by λ, an effective opening diameter of the optical scanning unit is denoted by M, a distance from the optical scanning unit to the light diffusion unit is denoted by L, and an arrangement pitch of the plurality of light diffusion channels is denoted by P, the light diffusion unit is configured so that the arrangement pitch becomes a value set on the basis of P≥(4λL)/(πM).