The present invention provides an LED illumination device including a base (4), at least one flexible circuit board (51) and a plurality of LEDs (52). The at least one flexible circuit board is used for covering the base. The LEDs are mounted on the flexible circuit board. The present invention utilizes a flexible circuit board that can conform to the base having a 360 degree curved surface and a 3D solid structure to efficiently change the viewing angle of the LEDs so as to provide 360 degree viewing angle. Furthermore, a single flexible circuit board can be utilized to cover the base to provide a 360 degree viewing angle. Therefore, the LED illumination device of the present invention can reduce manufacturing cost and simplify the manufacturing process.