Abstract: In order to develope oral cephalosporin exhibiting broad-spectrum activity, a series of cephalosporin derivatives (Ⅷ1～12) bearing 1,2,3-triazolylmethyl substituents on the C₃ position were synthesized. 7-Phenylacetamido-3-methyl-3-cephem-4-carboxylic acid (Ⅰ) was employed as starting material and converted to Ⅷ by procedures of esterification and oxidation, bromination, azido-substitution, dipolar cycloaddition, deprotection, cleavage, and condensation. Minimum inhibitory concentra tion (MIC) values in vitro showed that Ⅷ_2～4.9～11 had a wide antibacterial spectrum against Gram positive and Gram negative bacteria and possessed high activities. Further biological evalution and the study of oral absorption for the six compounds will be performed.