Vancomycin is a glycopeptide antibiotic separated from streptomycete, having been used as the first choice to treat methicillin-resistant Staphylococcus aureus infection so far. The studies show that because of the individual difference in the metabolism of vancomycin, it is difficult to get the trough concentration of pediatric patients severely ill or complicatedly infected to reach the target range (15—20 mg/L). However, with the help of therapeutic drug monitoring (TDM) of vancomycin and the pharmacokinetic/pharmacodynamic parameter (PK/PD) mode, the PK/PD parameters to achieve the precise control can be acquired by using the Bayes feedback. By a stretched review from clinical medication guide of vancomycin to the latest evidence from research, this paper fully demonstrates that renal function, weight, age, and disease state are the principal parameters to impact pediatric patient’s vancomycin metabolism and that the area under the concentration-time curve divided by the minimum inhibitory concentration (AUC/MIC) ≥ 400 is the better cut-off value to determine vancomycin efficacy and toxicity.