Objective lt;brgt;To evaluate the efficacy of arteriovenous sheathotomy on treatment of branch retinal vein occlusion (BRVO). lt;brgt; lt;brgt;Methods lt;brgt;Six consecutive patients (6 eyes) with BRVO underwent par plana vitrectomy, po lt;brgt;sterios vitreous cortex separation, arteriovenous sheathotomy for BRVO. The foll lt;brgt;owup period was within 3～12 months. Postoperative examinations included color fundus photography, fundus fluorescein angiography(FFA), optical coherence tomography(OCT) and multifocal electroretinography (mERG). lt;brgt; lt;brgt;Results lt;brgt;Increasing downstream blood flow in proximal past of compressed venule was promptly observed during the procedures of incision of the advential sheath of blood vessel, and separating and elevating the ateriole from the venule in all the operations in this series. Visual acuities improved postoperatively in 5 patients, and the best corrected visual acuity was 1.5. The examination of FFA showed obvious absorption of retinal hemorrhage, and leakage of dye was reduced, while large areas of capillary closure in retinas distal to the sheathotomy site were found 3 months after operation in 3 patients. OCT revealed disappearance or lightening of macular edema. mERG showed that the response amplitude of retina including the macular area was obviously higher after the operation. There was recurrent vitreous hemorrhage necessitating further surgery in one patient. lt;brgt; lt;brgt;Conclusion lt;brgt;The operation of arteriovenous sheathotomy for the treatment of BRVO is much beneficial to improve patient′s visual acuity, downstream blood flow and macular affections, although the improvement of retinal reperfusion of the retina is not obvious. lt;brgt; lt;brgt;(Chin J Ocul Fundus Dis,2002,18:6-9)