Purpose This study aims to evaluate the clinical features of adenoma of the retinal pigment epithelium (RPE) and eye-sparing treatment for it. Methods The patients underwent measurement of visual acuity and intraocular pressure, slit-lamp examination, ophthalmoscopy, fluorescein fundus angiography (FFA), indocyanine green angiography (ICGA), color Doppler imaging (CDI), and magnetic resonance imaging (MRI). The tumors were endoresected and studied histopathologically. Results Of the 16 Asian patients, 15 had RPE adenoma and 1 had RPE adenocarcinoma. Visual acuity decreased in three cases, mainly due to the macular detachment. All tumors were solitary and unilateral and measured from 1.7 x 3.2 x 2.4 to 9.3 x 8.0 x 6.6 mm(3). The tumor was located in the macular area in 2 patients, in the juxtapapillary area in 1 patient, and in the peripheral fundus in 13 patients. The tumors were yellow-pink in 3 patients and brown in 13 patients. The tumors showed hypofluorescence in early stage and mottled hyperfluorescence with prominent leakage in late stage on fluorescein angiography. CDI demonstrated arterial blood signals within tumor, and MRI demonstrated hyperintensity and hypointensity in the T1- and T2-weighted images, respectively. The tumors were positive for S-100, neuron-specific enolase (NSE), CK, epithelial membrane antigen (EMA), and vimentin; occasionally positive for melanin-A; and usually negative for melanoma-specific antigen HMB45 and synaptophysin (Syn). The endoresection surgery was performed in all 16 patients by the microinvasive vitrectomy for the excision of intraocular tumors and reconstruction of the eyeball. The follow-up time was 1.5-13 years (mean, 5 years). No tumor recurrence occurred, and the retina remained attached in 16 eyes. Conclusions RPE-derived adenomas are rare and difficult to diagnose clinically. Local resection by the mircoinvasive vitrectomy is a feasible alternative treatment for RPE adenoma.