Background: Diabetic macular oedema can occur at any stage of retinopathy and is typically characterized by retinal thickening and leakage of extracellular fluid, which are linked with hypoxia and up regulation of vascular endothelial growth factor (VEGF). Objective: The aim of this study was to compare central macular thickness using optical coherence tomography (OCT) between Ranibizumab 0.5 mg monotherapy vs Ranibizumab 0.5 mg combined with laser based on mean average change in best-corrected visual acuity (BCVA) over 6 months in diabetic macular edema (DME). Patients and methods: The study was carried out on forty eyes of patients aged 30-75 years old, with type 1 or 2 diabetes mellitus and have visual impairment due to DME. The patients were selected from the Outpatient Ophthalmology Clinic of Aswan University Hospital. Results: Visual acuity measured as log MAR values in Group A, when comparing the baseline visual acuity with that at the end of follow-up period, there was a significant improvement in vision. Some patients achieved improvement of two lines at the end of six months. In Group B, there was a significant improvement in vision when comparing the baseline reading with the six months reading with an average gain in visual acuity of two or more lines. The central macular thickness improved in both groups without statistically significant difference between them in the first three months post-injection. However, the combined group achieved the highest reduction in the macular thickness at the end of follow-up period. Conclusion: Ranibizumab monotherapy provided significantly superior benefit over standard-of-care laser in patients with visual impairment due to DME being rapidly improved and sustained BCVA over the 6-month treatment period.