The synthesis of antioxidant Tert butyl hydroquinone bis phosphite ester four(2,4-ditertbutyl phenol) ester hadbeen studied by esterification of 2,4-ditertbutyl phenol, Tert butyl hydroquinone and phosphorus trichloride. The targetproduct was characterized by FTIR Spectrometer and1 H NMR. The reaction conditions were optimized. The yield was 73.1%.