An image display device comprising: a light source; an image generator that modulates a light beam emitted by the light source and generates image light; and a projection optical system (30, 230, 330, 430, 530, 630) that includes a first lens system that has a positive refractive power as a whole, and refracts the generated image light, a first reflection optical system that includes two or more reflection surfaces (Mr1, Mr2), each reflection surface (Mr1, Mr2) being a surface from which the image light refracted by the first lens system is reflected, a second lens system that has a positive refractive power as a whole, and refracts the image light reflected from the first reflection optical system, and a second reflection optical system that includes a concave reflection surface from which the image light refracted by the second lens system is reflected to be directed to a projected-onto object onto which projection is performed, wherein a first intermediate image of an image made up of the image light, is formed in a first intermediate image-formation plane situated between the image generator and the first reflection optical system, a second intermediate image of the image made up of the image light, is formed in a second intermediate image-formation plane situated between the first reflection optical system and the second lens system, and a third intermediate image of the image made up of the image light, is formed in a third intermediate image-formation plane situated between the second lens system and the second reflection optical system; or a first intermediate image of an image made up of the image light, is formed in a first intermediate image-formation plane situated between the image generator and the first reflection optical system, a second intermediate image of the image made up of the image light, is formed in a second intermediate image-formation plane situated between a first reflection surface and a second reflection surface that are included in the two or more reflection surfaces (Mr1, Mr2), and a third intermediate image of the image made up of the image light, is formed in a third intermediate image-formation plane situated between the second lens system and the second reflection optical system. a light source; an image generator that modulates a light beam emitted by the light source and generates image light; and a projection optical system (30, 230, 330, 430, 530, 630) that includes a first lens system that has a positive refractive power as a whole, and refracts the generated image light, a first reflection optical system that includes two or more reflection surfaces (Mr1, Mr2), each reflection surface (Mr1, Mr2) being a surface from which the image light refracted by the first lens system is reflected, a second lens system that has a positive refractive power as a whole, and refracts the image light reflected from the first reflection optical system, and a second reflection optical system that includes a concave reflection surface from which the image light refracted by the second lens system is reflected to be directed to a projected-onto object onto which projection is performed, wherein a first lens system that has a positive refractive power as a whole, and refracts the generated image light, a first reflection optical system that includes two or more reflection surfaces (Mr1, Mr2), each reflection surface (Mr1, Mr2) being a surface from which the image light refracted by the first lens system is reflected, a second lens system that has a positive refractive power as a whole, and refracts the image light reflected from the first reflection optical system, and a second reflection optical system that includes a concave reflection surface from which the image light refracted by the second lens system is reflected to be directed to a projected-onto object onto which projection is performed, wherein a first intermediate image of an image made up of the image light, is formed in a first intermediate image-formation plane situated between the image generator and the first reflection optical system, a second intermediate image of the image made up of the image light, is formed in a second intermediate image-formation plane situated between the first reflection optical system and the second lens system, and a third intermediate image of the image made up of the image light, is formed in a third intermediate image-formation plane situated between the second lens system and the second reflection optical system; or a first intermediate image of an image made up of the image light, is formed in a first intermediate image-formation plane situated between the image generator and the first reflection optical system, a second intermediate image of the image made up of the image light, is formed in a second intermediate image-formation plane situated between a first reflection surface and a second reflection surface that are included in the two or more reflection surfaces (Mr1, Mr2), and a third intermediate image of the image made up of the image light, is formed in a third intermediate image-formation plane situated between the second lens system and the second reflection optical system.