Abstract: A light-emitting device of a light-emitting diode (LED) and a manufacture method thereof are provided. The light-emitting device includes a post-like metal material, a printed circuit board, conductors, insulators, light-emitting diodes, wires, and an encapsulating material. The light-emitting device has through holes, in which conductors are disposed and surrounded with the insulators. One end of each conductor is connected to the printed circuit board to form a composite structure heat-dissipation substrate. The light-emitting diodes are disposed on the post-like metal material, connected to the conductors via the wires, and encapsulated by the encapsulating material. Furthermore, the light-emitting diodes, the wires, and the encapsulating material can be combined into a light-emitting unit. Moreover, red, blue, and green light-emitting diodes can be combined and the color of output light thereof can be adjusted by controlling the input signal.