Abstract: Cefathiamidinum is a new broad-spectrum semisynthetic cephalosporin antibiotic developed in china. In this paper the pharmacokinetics of cefathiamidinum and the effect of probenecid were studied in seven healthy adults.Post-infusion serum drug concentration versus time curve was fitted to two-compartment open model with first order elimination. However, the serum drug level data after intramuscular administration was adequately fitted to one-compartment open model with first order absorption and elimination. The pharmacokinetics of cefathiamidinum was complicated with the simultaneous administration of probenecid. After pharmacokinetic analysis it was considered that probenecid can competitively inhibit the urinary excretion of cefathiamidimum. The peak trevel and the area under Cxt curve increased significantly in the presence of prebenecid, and its probable clinical significance was discussed.The pharmacokinetic characteristics of cefathiamidinum were discussed and compared with those of other members, of the commonly used cephalosporin series.