The invention discloses an LED (light-emitting diode) package device which comprises an LED support, a fluorescent glue layer, a chip and a golden wire. The LED support comprises a metal substrate, a white reflecting plastic layer and a primary coat transition layer, the primary coat transition layer is excellent in compactness and viscidity, one surface of the metal substrate is coated with the primary coat transition layer, and the surface of the primary coat transition layer and part of surface of the metal substrate are coated with the white reflecting plastic layer by the aid of a bowl cup shape. The invention further correspondingly discloses a preparation method of white LED package device. The LED package device can adapt various high-temperature and high-humidity environments, and LED products are high in reliability. For the preparation method of the LED package device, a process is simple and easy to practice. Based on improvement of product quality, preparation efficiency is high, and preparation cost is reduced.