Purpose: To evaluate the occurrence of cystoid macular oedema (CME) and to identify changes in the thickness in the central macula (CMT) using spectral domain optical coherence tomography (SD- OCT) after uneventful phacoemulsification surgery. Method: In this prospective study, 150 patients of cataract, were subjected to examination by SD-OCT one day before and 1, 4, and 12 week post operatively to detect any changes in foveal thickness and presence of cystoid macular oedema. The results were analyzed and correlated with the visual acuity. Results: 150 patients were included in this study. Out of these 150 patients, 86(57.33%) were males and 64(42.67%) were females, with mean age being 65.33±6.82 years. None of them had any pre-existing ocular pathology. The average central macular thickness (CMT) measured preoperatively was 243.35± 19.508. Out of 150 patients, 5 (3.33%) patients were detected to have post operative CME. Decline in visual acuity was noticed in those patients who developed post operative macular oedema, and improvement was noted by the end of 12 weeks. Mild increase in macular thickness (±35µ) was noticed even in those eyes which did not develop macular oedema. Conclusion: CME can develop even in patients who had undergone uncomplicated cataract surgery. SD OCT is a reliable and non invasive method to detect the changes in the macula at early stage and helps in accurate diagnosis.