Background: Diabetic macular edema (DME) is the most common cause of visual impairment in diabetic patients. Disruption of both components of blood retinal barrier (BRB) leads to increased accumulation of fluid within the intraretinal layers of the macula. Optical coherence tomography (OCT) enables obtaining the high resolution cross-sectional images (tomograms) of the human retina in a noninvasive manner. It can detect the response of the patient to different modalities of treatment upon some factors will be discussed in that issue. Objective: Assessment of different patient's response to different modalities of treatment in patients with diabetic macular edema using the OCT.  Patients and methods: In this study, we tested 50 eyes of 35 patients with diabetic macular edema. They were evaluated using the spectral domain OCT before intravitreal injection of antiVEGF and after 1 and 6 months from 1st injection. Results: The 50 eyes with diabetic macular edema were 22(44%) males and 28(56%) females. The age of patients ranged from 48 to 66 years with a mean of 56.48±4.98, 6(12%) of them had diabetes type one and 44(88%) had diabetes type two. Twelve (24%) were treated by insulin, 9(18%) by tablets, and 29(58%) used both insulin and tablets. As regards other co-morbidities, 12(24%) had hypertension, 6(12%) had nephropathy, and 8(16%) had ischemic heart diseases.      The fifty eyes were 21(42%) right, and 29(58%) left. Eleven (22%) of patients had intraretinal cyst, 11(22%) of patients had subfoveal neuroretina detachment, external limiting membrane (ELM) was disrupted in 10(20%), and inner segment/outer segment (IS/OS) was disrupted in 18(36%).      There was a statistically significant difference between the mean of Logarithim of the Minimum Angle of Resolution best corrected visual acuity (log MAR BCVA) (0.71±0.32) and the central subfoveal thickness mean (470.70±99.14) pre injection, and 1-month post injection log MAR BCVA mean (0.48±0.23), and the central subfoveal thickness mean (386.72±85.92) (𝑃 < 0.001). BCVA and the central subfoveal thickness continued to improve progressively until the end of the 6-month follow-up period where they were 0.42 ± 0.29 and 384.64 ± 97.69 respectively and that was statistically significant (𝑃 < 0.001). Conclusion: OCT characteristics of different DME patterns at baseline can predict morphological features and timing of DME recurrence. OCT characteristics at follow-up can be used in prognosis of DME.