OBJECTIVE：To optimize each link of work flow in PIVAS of our hospital，and to improve the quality of drug dispensing. METHODS：Lean management was applied in each link of PIVAS，the problems that influenced the quality of drug dispensing were found out，and then countermeasures were put forward for continuous improvement. Related indicators were compared 10 months before and after management in order to evaluate improvement effects. RESULTS & CONCLUSIONS：Through implementing various measures in PIVAS，such as optimizing prescription checking software，rational staff arrangement，staff training， visual management，“5S”management，equipment innovation and careful-chosen consumptive material，the average daily working time reduced from 8 h to 6.5 h，the staff number from 52 to 48，the error rate from 1.76‰ to 0.84‰，the average drug inventory turnover days from 7.42 days to 4.93 days，and the prescription failure rate from 1.28‰ to 0.59‰. Lean management reduces various kinds of mistake，improves work efficiency，increases dispensing quality，strengthens rationality of drug use and ensures the effectiveness and safety of clinical drug use.