Abstract: An illumination system capable of realizing a color image without a color wheel, and a projection system employing the illumination system. The illumination system includes first, second, and third light emitting devices and first and second hologram devices. The first, second, and third light emitting devices emit light beams having different wavelengths. The first and second hologram devices are disposed in an “X” configuration at an angle with respect to the first, second, and third light emitting devices and transmit or reflect incident light depending on the wavelength of the light. The projection system further includes a display device, and a projection lens unit. The display device processes beams incident in one direction via the first and second hologram devices, according to an input image signal, and forms an image. The projection lens unit enlarges and projects the image formed by the display device on a screen. The illumination system and the projection system can realize a wide color gamut.