An LED light device and a circuit preparation method thereof are provided. The LED light device includes a base, an LED light unit, and a lamp shade. The LED light-emitting unit and the lamp shade are arranged on the base. The lamp shade covers the LED light-emitting unit inside. The circuit preparation method includes following steps of: providing a base which is a physical entity having a three-dimensional structure on the surface thereof; coating a circuit layer on the base surface through a programmable coating equipment, manual coating or the combined mode, wherein the circuit layer is a liquid or powder coating containing metal materials, and the thickness of the circuit layer is 20 μm or more; baking the base coated with the circuit layer at the high temperature of 100-1,000° C. until the circuit layer is dried; and obtaining a base having a three-dimensional circuit after cooling.