Purpose: We report the successful surgical treatment of a case of spontaneous complete anterior crystalline lens luxation in a patient affected by retinitis pigmentosa (RP), associated with elevated intraocular pressure and pupillary block. Additionally, we review the current literature regarding the association between ectopia lentis and RP. Case description: A 44-year-old female RP patient presented to our emergency department reporting severe ocular pain in her left eye (LE) and sickness. She had no history of ocular trauma and did not report systemic disorders. The best corrected visual acuity at presentation was 1/20 in her LE, the intraocular pressure was 60 mmHg, and slit lamp examination showed in her LE a complete dislocation of the lens in the anterior chamber, with mydriasis, atalamia, and a pupillary block. The patient had been administered intravenous mannitol 18% solution and dorzolamide–timolol eye drops and was hospitalized for urgent lens extraction. Anterior segment optical coherence tomography and ultrasound biomicroscopy were performed before surgery. Decompressive 23-gauge pars plana vitrectomy and phacoemulsification were performed, and the capsular bag was removed due to marked zonular weakness, with deferred intraocular lens implant. Conclusions: Acute angle closure glaucoma in patients with RP may be rarely caused by spontaneous anterior lens dislocation. To our knowledge, this is the first report of spontaneous anterior lens dislocation in an RP patient, documented through photographs, anterior segment optical coherence tomography, and ultrasound biomicroscopy.