An optical fiber decoration device has various merits: small power consumption, no danger of fire, simple water-proof design and economical, battery can be used, excellent portability, long service life of light source, and no danger of destruction during transportation. The optical fiber decoration device is characterized by having an LED light source consisting of a plurality of LED's which are arranged at an end of optical fiber for emitting one or more colors and partially superimposed, enabling synthesis of colors. In FIG. 1, the optical fiber decoration device (I) includes an LED light source unit (2) and an optical fiber (1a). The distance L between the LED light source (2) and the optical fiber is 5 to 100 mm. Red, blue, and green LED's are used to realize multiple colors. The optical fiber decoration device can be used for signboards, outdoor decorations, bus advertisement, indoor decorations, decorations in an aquarium, unit type Christmas trees, clothes, and the like.