Pediatric sepsis syndrome is one of the most common reasons for pediatric intensive care unit hospitalization (PICU). Cefoperazone/sulbactam is a time-dependent beta-lactamase inhibitor combination which has been widely used in the treatment of sepsis. But the pharmacokinetic (PK) and pharmacodynamic (PD) data of cefoperazone/sulbactam are unknown in children with sepsis. The present work aimed to determine whether the usual dosing regimens of cefoperazone/sulbactam (1 hour infusion, 50 mg kg-1, every 12 hours) were suitable for these patients in PICU. A total of fourteen patients were enrolled and the PK parameters were estimated by non-compartmental analysis using WinNonlin software. The t1/2 and AUC0-12 of cefoperazone and sulbactam were 3.60 and 1.77 h, and 900.97 and 67.68 h μg mL-1, respectively. The Vd and CL of cefoperazone and sulbactam were 1.65 L and 5.16 L, and 17.41 mL min-1 and 122.62 mL min-1, respectively. The probability of target attainments (PTAs) of cefoperazone at different minimum inhibitory concentrations (MICs) based on the percentage time that concentrations exceed the minimum inhibitory concentration (% T > MIC) value were performed by Monte Carlo simulation and PTA was >90% at MICs ≤16 μg mL-1. The PK/PD profile of dosing regimens tested will assist in selecting the appropriate cefoperazone/sulbactam regimens for these patients. At a target of 80% T > MIC, the usual dosing regimens can provide good coverage for pathogens with MICs of ≤32 μg mL-1. The ratio between cefoperazone and sulbactam at 1 : 1 may be more suitable in pediatric sepsis. Individual dose and therapeutic drug monitoring in clinical practice will help achieve the best therapeutic effect while minimizing toxicity.