In an adult Japanese monkey (Macaca fuscatus), intravenous injections of adrenalin were repeated daily: 0.125 mg/kg for 7 days and 0.375 mg/kg from the 11th day on. In a cynomolgus monkey (Macaca irus), daily injections were carried out with intravenous adrenalin (0.11 mg/kg for 12 days and a double dose from the 13th day on) and also with intramuscular prednisolone. After the 39th injection in the former and after the 32nd injection in the latter monkey, disciform serous retinal detachment was seen to occur in the posterior pole region, and fluorescein angiography revealed multiple dye leakage spots at the level of the retinal pigment epithelium. Sometimes these changes subsided, but on continuing injections, these changes recurred on new locations. Two types of fluorescein leakage spots were recognized, i.e. ink blot type with progressive simple enlargement with time and the mushroom or jet type showing these patterns during enlargement. No abnormality was found in the optic disc, retinal vessels or in the choroidal circulation. The fluorescein angiographic findings were in close resemblance with those seen in the human central serous chorioretinopathy. It was discussed that these fundus changes of the monkey eye produced by repeated adrenalin injections would serve as a good animal model of the human disease.