Chronic dacryocystitis and lacrimal duct obstruction are common diseases in ophthalmology, and if not treated thoroughly, there is a risk of latent intraocular and extraocular infections. The principle of its treatment is to control the inflammation of the lacrimal sac and to restore or establish a lacrimal sac-to-nasal drainage channel. Tear sac nasal anastomosis is the traditional treatment measure, which is done by ophthalmologists, but the posterior face is scarred and damaged by the surgery, and the surgery is also difficult and bleeds more during the operation. It is difficult for some patients to accept. Endoscopic transnasal lacrimal sac rhinoplasty is simpler, easier and safer than traditional percutaneous surgery. There are no facial scars and few surgical complications. It can also correct pre-existing nasal and sinus disorders or anatomical abnormalities that may affect the drainage of the lacrimal sac and lead to surgical failure. It is currently the best surgical procedure for the treatment of chronic dacryocystitis and nasolacrimal duct obstruction. It has many advantages compared to traditional surgery. Our department has been performing this technique for many years with good results.