Background: glaucoma is the most common cause of irreversible blindness. Primary open angle glaucoma (POAG) is the most commonly diagnosed form. Pattern electroretinogram emerged as a promising tool for diagnosing of early glaucoma. Aim of the work: the present study aimed to assess the role of pattern electroretinogram in differentiating between patients with early glaucoma and normal controls. Methodology: this study included 25 early glaucoma patients and 25 normal controls. They were undergone into careful history taking, complete ophthalmic examination and investigations by using PERG, SD- OCT and perimetry. Results: regarding the comparison we found reduction in amplitude of P50 and N95 between early glaucoma patients and normal controls.