ObjectiveTo evaluate the effect of Lean Six Sigma （LSS） on intervening in medical waste management in a hospital, and evaluate the intervention effect.MethodsMedical waste disposal in  inpatient departments and operating rooms in a tertiary firstclass hospital were investigated, 13 inpatient departments  were randomly chosen for study. December 2014March 2015 was preintervention  stage, baseline data of medical waste management were surveyed,  AprilJuly 2015 was postintervention stage, LSS DMAIC (define, measure, analyze, improve, control) process was used to standardize process of the classification and disposal of medical waste, management effect was evaluated.ResultsAnalysis on factors influencing the cost of medical waste disposal revealed that there were 7 influencing factors, and that presenting 4 progressive structures, undefined responsibility of administration department was the root cause, which led to the different standards for medical waste classification, and eventually influenced the cost of medical waste disposal. The qualified rates of medical waste classification in inpatient departments and operating rooms increased from 69.22% and 71.88% before intervention to 80.42% and 81.00% after intervention respectively，difference were both significant（both P＜0.01）; medical waste weight in inpatient departments decreased from (1.11±0.14) kg/bedday to (0.91±0.18) kg/bedday, and that in operating room decreased from (10.77±0.33)kg/bedday to (7.26±1.04) kg/bedday(both P<0.05). The benefitcost ratio was 6.09, that is, 1yuan investment could save 6.09 yuan.ConclusionLSS management method can effectively reduce medical waste weight and cost of every hospitalization day,  and it has certain health economic value.