A projection device, comprising a first display, a second display, a third display, a light-combining module, a first angle selector, a second angle selector, a third angle selector, and a projection lens, wherein: the first display, the second display, and the third display are respectively adapted to provide a first image beam, a second image beam, and a third image beam; the light-combining module comprises a first light-incident surface, a second light-incident surface, a third light-incident surface, and a light-outgoing surface; the first angle selector is provided between the first display and the light-combining module, the second angle selector is provided between the second display and the light-combining module, and the third angle selector is provided between the third display and the light-combining module; and the projection lens is provided on one side of the light-outgoing surface of the light-combining module, and the projection lens is adapted to project the first image beam, the second image beam, and the third image beam out of the projection device, wherein: after the first image beam, the second image beam, and the third image beam have passed through the first angle selector, the second angle selector, and the third angle selector respectively, the first image beam, the second image beam, and the third image beam are transmitted to the projection lens by the light-combining module, the projection device further comprises a first anti-reflection layer, a second anti-reflection layer, and a third anti-reflection layer, wherein the first anti-reflection layer, the second anti-reflection layer, and the third anti-reflection layer are respectively disposed on the first light-incident surface, the second light-incident surface, and the third light-incident surface of the light-combining module. the first display, the second display, and the third display are respectively adapted to provide a first image beam, a second image beam, and a third image beam; the light-combining module comprises a first light-incident surface, a second light-incident surface, a third light-incident surface, and a light-outgoing surface; the first angle selector is provided between the first display and the light-combining module, the second angle selector is provided between the second display and the light-combining module, and the third angle selector is provided between the third display and the light-combining module; and the projection lens is provided on one side of the light-outgoing surface of the light-combining module, and the projection lens is adapted to project the first image beam, the second image beam, and the third image beam out of the projection device, wherein: after the first image beam, the second image beam, and the third image beam have passed through the first angle selector, the second angle selector, and the third angle selector respectively, the first image beam, the second image beam, and the third image beam are transmitted to the projection lens by the light-combining module, the projection device further comprises a first anti-reflection layer, a second anti-reflection layer, and a third anti-reflection layer, wherein the first anti-reflection layer, the second anti-reflection layer, and the third anti-reflection layer are respectively disposed on the first light-incident surface, the second light-incident surface, and the third light-incident surface of the light-combining module. after the first image beam, the second image beam, and the third image beam have passed through the first angle selector, the second angle selector, and the third angle selector respectively, the first image beam, the second image beam, and the third image beam are transmitted to the projection lens by the light-combining module, the projection device further comprises a first anti-reflection layer, a second anti-reflection layer, and a third anti-reflection layer, wherein the first anti-reflection layer, the second anti-reflection layer, and the third anti-reflection layer are respectively disposed on the first light-incident surface, the second light-incident surface, and the third light-incident surface of the light-combining module.