The application relates to the technical field of projection, and discloses a projection device which can improve the brightness of projection imaging. Part of the projection device comprises: an LED light source, a color wheel, a light-equalizing rod, a convex lens, a first Fresnel lens, an LCD panel and a projection lens; a ray of target light emitted by the LED light source emits a target alternating light through the color wheel, and the target alternating light comprises five monochromatic lights including red light, green light, blue light, yellow light and white light, and the five monochromatic lights enter the light-equalizing rod for uniform treatment to emit an uniform light spot, the uniform light spot is imaged at the first Fresnel lens through the convex lens, then irradiated into the LCD panel, and projected by the projection lens.