Abstract Background: Diabetic retinopathy is one of the most important challenges that faces the diabetic patients, simply it is a microangiopathy of the retina which leads to impairment of visual abilities if neglected, consists of many factors such as vascular walls changes and alterations in blood physiological criteria. These factors leads to capillary occlusion and so to fluid leakage and retinal ischemia. Aim of Study: Evaluation of the superiority and sensitivity of the OCT angiography technique over fundus fluorescein angiography in detection of clinically undetected neovascu-larization. Patients and Methods: Prospective, observational study. Sample consists of 30 eyes of patients presented to the outpa-tient clinic with severe non-proliferative diabetic retinopathy and clinically undetected neovascularizations. Results: Results showed that FFA and OCTA were equal in diagnosing 23 eyes as Severe NPDR with no obvious proliferative activity in all retinal slabs. As well as OCTA could confirm the FFA diagnosis of suspected PDR in 6 eyes in a form of NVDs. However, OCTA was superior to FFA in diagnosing PDR and detecting neovessles (mainly NVDs) in 1 eye. In brief, this study revealed a highly significant corre-lation between OCT and FFA which means that OCTA shows a great utility in the clinical practice in discovering invisible neovascularization especially in the central part of the retina and to predict the progression of diabetic retinopathy, which in turn affects the management decisions and prevents unfa-vorable complications. Conclusion: This study demonstrated that Conventional OCTA is very useful clinically in evaluation of new vessels formation mainly in the central retina, however FFA still owns the upper hand in assessment of proliferative activity in the peripheral retina.