BACKGROUND Here, we describe a patient who exhibited pseudophakic angle closure due to vitreous block following ureteroscopic lithotripsy under general anesthesia. METHODS A 57-year-old Thai man presented with sudden eye pain and blurring of vision in the left eye following ureteroscopic lithotripsy under general anesthesia. The patient had a history of coconut hit into his left eye which resulted in traumatic anterior lens subluxation, for which he had undergone phacoemulsification and scleral-fixated intraocular lens implantation in the left eye. Prior scleral fixation procedure, anterior vitrectomy was not performed. Clinical examination showed mushroom-shaped vitreous in the anterior chamber with absolute pupillary block, which had resulted in acute angle closure. Thus, topical and oral antiglaucoma medications were administered to achieve normal intraocular pressure in the left eye, followed by laser peripheral iridotomy in that eye. The anterior chamber depth was successfully increased. Limited anterior vitrectomy by a pars plana approach was performed to prevent recurrent angle closure. The patient's vision improved and his intraocular pressure remained controlled without any antiglaucoma medication. CONCLUSIONS Vitreous block can occur in patients with pseudophakia, especially in the presence of a ruptured posterior capsule. Cautious intraoperative anterior vitrectomy and surgical iridectomy are warranted. General anesthesia may contribute to the onset of vitreous block in susceptible patients.