A projection-type image display apparatus for projecting an image, enlargedly, onto a projection surface , comprising: an image display element ; a lens group, being disposed downstream of said image display element , comprising therein, a first lens group made up with a plural number of lenses, including, at least, a refractive lens, having a positive power or a negative power and being rotationally symmetric in a surface configuration thereof, and a second lens group made up with a plural number of lenses, including, at least, a rotationally asymmetric lens, the second lens group being disposed downstream of the first lens group , the lens group being arranged to emit the light from the image on the image display element ; and a reflection mirror for reflecting the light from said lens group, thereby to project the light obliquely onto said projection surface ; wherein a ratio of a diagonal size (Lo) of a projection image projected on said projection surface with respect to a distance (Lp) of said projection image from a central portion of said reflection mirror is greater than two; characterized in that : said reflection mirror has a free curved reflection surface which is rotationally asymmetric directed to said projection surface ; and a normal line to the image display element surface is inclined by 1.1 - 2.0° to the optical axis of said lens group, the direction of inclination being opposite to the direction in which the projection surface is positioned. an image display element ; a lens group, being disposed downstream of said image display element , comprising therein, a first lens group made up with a plural number of lenses, including, at least, a refractive lens, having a positive power or a negative power and being rotationally symmetric in a surface configuration thereof, and a second lens group made up with a plural number of lenses, including, at least, a rotationally asymmetric lens, the second lens group being disposed downstream of the first lens group , the lens group being arranged to emit the light from the image on the image display element ; and a reflection mirror for reflecting the light from said lens group, thereby to project the light obliquely onto said projection surface ; wherein a ratio of a diagonal size (Lo) of a projection image projected on said projection surface with respect to a distance (Lp) of said projection image from a central portion of said reflection mirror is greater than two; characterized in that : said reflection mirror has a free curved reflection surface which is rotationally asymmetric directed to said projection surface ; and a normal line to the image display element surface is inclined by 1.1 - 2.0° to the optical axis of said lens group, the direction of inclination being opposite to the direction in which the projection surface is positioned. said reflection mirror has a free curved reflection surface which is rotationally asymmetric directed to said projection surface ; and a normal line to the image display element surface is inclined by 1.1 - 2.0° to the optical axis of said lens group, the direction of inclination being opposite to the direction in which the projection surface is positioned. <EOS>