A mucosal autograft composed of agger nasi cell mucosa was used to reconstruct the lacrimal sac mucosa in a young woman with a cicatrised lacrimal sac and obstructed nasolacrimal system. The patient had undergone a previous external dacryocystorhinostomy (DCR), dacryocystectomy and revision mechanical endonasal DCR. There was persistent epiphora and at further mechanical endonasal (MEN) DCR it was noted that only a small cuff of lacrimal sac mucosa around the common canaliculus was present. To achieve a mucosal anastomosis, the agger nasi cell mucosa was removed from the cell and placed as a free mucosal graft around the common canalicular opening. Apposition with the nasal mucosa was completed with flaps from the lateral nasal wall mucosa. Postoperatively, the patient is asymptomatic with a freely draining ostium at 18 months of follow-up.