Background: Cataract surgery with phacoemulsification is one of the most common surgical procedures performed today .Compared to people without diabetes, diabetic patients have been shown to have an elevated risk of developing cataracts. Cataract surgery in diabetics is indicated not only to improve visual acuity, but also to allow assessment and treatment of fundus changes. Even in the absence of diabetic retinopathy, diabetes mellitus has been found to have about twice the occurrence rate of pseudophakic CME. Objectives: This study was done to document any subsequent post-phacoemulsification macular edema (PPME) as postoperative sequelae in the diabetic versus non-diabetic nuclear senile cataract patients. Methods: This study was conducted on patients complained from visually significant immature senile cataract in ophthalmology department at Sohag university hospital between January 2018 and December 2020.Corrected distance visual acuity, Keratomerty, refraction, slit-lamp examination, macular optical coherence tomography (OCT) and biometry. Phacoemulsification was performed to all patients by stop and shop technique. The macular OCT changes were documented preoperatively and at postoperative month 1, 3, 6. Results: 64 eyes of 64 patients with visually significant senile cataract were included 32eye of them were diabetics, (33 males, and 31 females), our study documented four cases of the entire 64 eyes (6%) complicated with PPME in groups A and B at the postoperative month 1. Both A and B groups exhibited the same incidence of postoperative macular edema i.e. two (6%) cases in each group. Conclusion: Our outcomes confirmed that there was a similar probability of PPME occurrence in both non-diabetic and diabetic patients as this probability was mostly related to the surgical procedure itself. Meanwhile, the non-diabetic PPME exhibited rapid and complete recovery within one month in comparison to the diabetic PPME that exhibited gradual and incomplete recovery during the postoperative six months follow-up period.