AIM:To investigate the operative effect of epiphora caused by plica semilunaris laxation.METHODS:Thirteen cases (18 eyes) underwent the chalasia plica semilunaris resection from June of 2007 to June of 2009. Postoperative symptoms were evaluated; the conjunctiva was observated by slit-lamp,so was tasting of chloramphenicol test. RESULTS:Symptoms disappeared or were improved in 15 eyes (83%) among 18 eyes 4 weeks after operation,and disappeared or were improved in 11 eyes among 13 eyes 12 weeks after operation,During the post-operative slitl-amp examination 4 weeks after operation,plica semil-unaris laxation was completely eliminated in 16 eyes (89%) with blockage of puncta relieved among 18 eyes,and 12 weeks after operation,plica semilunaris laxation was completely eliminated and the blockage of puncta were relieved in 12 eyes among 13 eyes (92%); chloramphenicol tasting tests returned to normal in 14 eyes (78%) of 18 eyes 4 weeks after operation,and 10 eyes (77%) of 13 eyes returned to normal 12 weeks after operation.CONCLUSION:The operation of plica semilunaris laxation resection is easy,safe and effective.