Abstract: To develop new synthetic process of ceftriaxone sodium, 7-amino-3-［(2, 5-dihydro-6-hydroxy-2-methyl-5-oxo-1, 2, 4-triazin-3-yl)thiomethyl］-3-cephem-4-carboxylic acid(7-ACT)was synthesized from 7-aminocephalosporanicacid(7-ACA)by reaction with 2, 5-dihydro-6-hydroxy-2-methyl-3-mercapto-5-oxo-1, 2, 4-triazine(TTZ)under the catalysis of BF₃/C₂H₃N. Ceftriaxone was prepared from 7-ACT by condensation with 2-(2-amino-4-thiazolyl)-2-methoxyiminoacetic thiobenzothiazole ester(AE)using triethylamine as catalyst. After removing the by-product 2-mercaptobenzothiazole(M)through filtration, the filtrate was treated with sodium acetate to give ceftriaxone sodium. This improved process eliminates the working procedure for separating compound M from the mother liquor, and has the advantages of less solvent consumption and convenient operation, and has been successfully used in commercial production.