OBJECTIVE： To explore the role of clinical pharmacist in individualized treatment for osteosarcoma patients with periprosthetic joint infection （PJI）. METHODS： An osteosarcoma patient was admitted to our hospital and then suffered from PJI after operation. Clinical pharmacist adjusted the initial anti-infection plan and carried out pharmaceutical care according to the results of patients’ etiology and drug sensitivity. According to the PK-PD principle， combined with the therapeutic drug monitoring （TDM）， the dose of antibiotics was adjusted. With the occurrence of ADR， the antibiotic therapeutic regimen was adjusted again. RESULTS： The patient was administrated cefotiam for empiric therapy initially after the diagnosis of PJI. After obtaining the results of etiology and drug sensitivity， the clinical pharmacist suggested that vancomycin sensitive to penicillin-resistant Staphylococcus epidermidis should be used for targeted anti-infection treatment. After adjusting the dosage according to the steady-state valley concentration， the patient had slight liver function damage， accompanied with chest tightness and shortness of breath. After analysis， the clinical pharmacist considered the adverse drug reactions related to vancomycin， and again suggested that the patient should be treated with teicoplanin. After the doctor adopted the treatment plan recommended by the clinical pharmacist， PJI of the patient was effectively controlled， and the adverse reaction symptoms disappeared. The patient was effectively cured for PJI and discharged eventually. During the treatment period， the clinical pharmacist also carried out medication education for the drugs used by the patient. CONCLUSIONS： Clinical pharmacist should master the principle of antibiotic drug PK-PD theory and evaluate the clinical efficacy and safety of anti-infective drugs dynamically based on the guidance of TDM， so as to develop individualized anti-infection therapeutic regimen for osteosarcoma patient with PJI， improve the effect of clinical treatment and guarantee the safety of drug use.