OBJECTIVE:To improve the drug delivery procedures and reduce the defects occurred in drug delivery.METHODS:The five procedures of six sigma including defining,measuring,analyzing,improving and controlling were applied to improve the drug delivery in our hospital's single dose dispensing(UDD)center.RESULTS:Due to the application of the six sigma method,the defect rate of drug delivery dropped from 25.1%(before the initiation of the six sigma method)to 5%(after the initiation of the six sigma method),which was significant lower as compared before the initiation of the six sigma method.CONCLUSION:Six sigma method contributed to the reduction of defect rate of drug delivery,so it deserves to be widely used in each management link in UDD center so as to improve the quality of dispensing.