A technique for quantitative determination of biapenem in human blood plasma using HPLC with UV detection was developed to provide therapeutic drug monitoring in a hospital setting. Detection was made spectrophotometrically at 300 nm. The chromatographic procedure lasted 15 min. Precipitation with MeCN was used for sample preparation. The lower limit of quantification was 0.2 μg/mL. The methodology was validated for the main parameters. Linearity was observed over a wide concentration range from 0.5 to 100 μg/mL. The results made it possible to use the developed method for rapid determination of the biapenem content in patient blood plasma, which enabled personalization of the drug doses and increased the efficiency and rationality of antibacterial therapy.