A waterproof LED underground light contains: a housing, a circuit board, an LED light source, a surface cover, a tempered glass, and a sealing rubber ring. The housing is molded from plastics and is provided with a plate hiding groove, a plate placing position, a sealing groove and a fixed side. The circuit board is configured in the plate hiding groove. The light guide plate is configured in the housing. The LED light source is configured in the side face of the light guide plate. The surface cover is configured above the fixed side. The tempered glass is configured between the surface cover and the housing. The sealing rubber ring is configured between the surface cover and the housing.