Objectives: Using Ocular Coherence Tomography, the study aimed to examine the RNFL thickness of type diabetics, patients with Diabetic Retinopathy, and healthy persons. Methods: 101 patients from the outside patient department and the Retina department of Tertiary Eye Care Hospital participated in this research. The cross-sectional study design was used. Non-probability consecutive sampling was utilized as the sampling technique. Patients were selected according to inclusion criteria. Visual Acuity was assessed using an (ETDRS) Early Treatment Diabetic Retinopathy Study Visual acuity chart at a distance of 6m. After the Ophthalmological Examination was done by a doctor, Ocular Coherence Tomography (Heidelberg Spectralis) was performed to assess RNFL thickness. The association between different types of diabetic retinopathy, Type-2 Diabetes, Normal Healthy, and retinal RNFL thickness was determined using a one-way ANOVA test. Results: The age range of the participants was between 40 and 69 years, with a mean of 55.68 ±10.437 years. 15.3% had diabetes for 1 to 5 years. 24% had Diabetes for 6 to 10 yea 19.9% had a Diabetes duration of 19.9%. The RNFL thickness was significantly decreased in type 2 diabetics, NPDR, and PDR as compared to normal Healthy individuals (p<.001). Age and duration of diabetes were closely correlated with the retinal nerve fiber layer (p<0.001). Conclusion: This study indicated that the (retinal nerve fiber layer) RNFL was considerably thinner in all quadrants of diabetic retinopathy (NPDR, PDR), type 2 diabetics, and healthy persons. Age and duration of diabetes were significantly correlated with average RNFL thickness.