Underground diaphragm wall and construction method thereof

The invention provides an underground diaphragm wall and a construction method thereof. The underground diaphragm wall comprises a soil layer; connecting grooves are formed in the two ends of the prefabricated wall plate correspondingly, and storage grooves are symmetrically formed in the prefabricated wall plate; a plurality of grooves are symmetrically formed in the side wall of the prefabricated wall plate, a plurality of through holes are formed in the grooves, and the through holes communicate with the interior of the storage groove; a wall body; the wall body is poured on sealing mechanisms on the two sides of the prefabricated wall panel, the multiple clamping grooves are formed in the side wall of the prefabricated wall panel, the side wall of one end of each clamping groove is obliquely arranged, and the fixing rods are clamped in the clamping grooves; the rubber pad is installed on the side wall of the fixing rod, the communicating groove is formed in the side wall of the fixing rod, and the rubber