AIM:To investigate the therapeutic effect of KTP laser combined with new lacrimal drainage device for the treatment of lacrimal duct obstruction.METHODS:Lacrimal probe with needle core was penetrated into the lacrimal passage,and the KTP laser fibre was put into the passage to remove the obstruction.Unobstruction of lacrimal passage was confirmed by irrigation.Then,two ends of the lacrimal drainage tube were put into the nose through upper and lower puncta and reopened lacrimal duct.An permanent tie was made with the two ends of lacrimal drainage tube and excess tube was removed.Antibiotic eye drops was applied after the operation.The tube was removed 3 months later.RESULTS:Totally 426 cases (482 eyes) of lacrimal duct obstruction were treated in this way.445 eyes were cured successfully and 37 eyes failed,which accounted for 92.3% and 7.7% respectively.CONCLUSION:KTP laser combined with lacrimal drainage tube is a very simple way to treat lacrimal duct obstruction with the advantages of wide application,minimal tissue damage and no scar.Moreover,it is an outpatient surgery without pain,which takes only 5minutes.