An admission method of a full water cooling ultra-silence generator set comprises a soundproof box shell, a base, an internal combustion engine and an electrical machine. The internal combustion engine and the electrical machine are disposed on the space enclosed by the sound proof box shell and the base. The bracket is a rectangular tank and comprises a baseboard, an upper cover plate and a rectangular frame. The baseboard and the upper cover plate respectively cover the upper surface and the lower surface of the rectangular frame. The rectangular tank is provided with a plurality of beams. The beams divide the rectangular tank into multiple independent subsidiary cavities. A main beam I is provided with an air intake hole. Each beam is provided with an air hole. The upper cover plate is provided with an air outlet and an electronic device cooling insert hole. When the generator set works, the external air successively flows through the subsidiary cavities at all levels by the air hole in the bracket and the external air flows into the sound proof box shell through the air outlet. The admission method of the full water cooling ultra-silence generator set has an undoubted technical effect. Air admission is achieved while surface of the generator set and parts of electronic devices are cooled, and normal aspiration of the generator set is achieved while a good erasure effect is ensured.