Sulfur phosphate was synthesized through the reaction of n-butanol, iso-octanol and phosphorus pentasulfide in the absence of solvent. The reaction condition was optimized by variation of catalyst type, the feeding mode of phosphorus pentasulfide, reaction temperature, pressure and initial reaction emperature. In the mean time, the performance differences of the lubricating additive T202 prepared by sulfur phosphate catalysis was compared with that synthesized with old process. Experimental results showed that the optimal conditions was as follows: the catalyst 4, the phosphorus pentasulfide feeding mode was nine, the reaction temperature was 50～55 ℃, the pressure was 0.07 MPa, initial temperature was 40 ℃, the reaction time was 1 h. Under this condition, the achieved content of sulfur phosphate was up to 99.4%, the zinc content of the lubricating additive T202 prepared by sulfur acid was 11.76%, and the chroma was 0.