Purpose Occult macular dystrophy (OMD) is an unusual, inherited macular dystrophy characterized by a slowly progressive decline of visual acuity with normal fundus and fluorescein angiography (FA). The authors present a 43-year-old man who was diagnosed as having OMD because of the results of electrophysiological, psychophysical, optical coherence tomography (OCT) tests. Methods Routine ophthalmological evaluation, FA, visual field tests, electroretinographic examinations (EOG, ERG, PERG and mfERG recordings according to ISCEV standards) and foveal thickness measurements (OCT) were performed. Results Funduscopic examinations, FA, full field ERG as well as PERG results were all normal. In both eyes, the abnormalities were observed in static perimetry (relative central scotomas), mfERG (significant reduction of P1 amplitude in the central retinas) and OCT (significantly thinner foveal thickness). Conclusions A new case with OMD is added to preceding reports. The mfERG and OCT tests are important in detection of OMD patients. It can help in differential diagnosis of amblyopia, optic nerve diseases and non-organic visual disorders.