Background: Composite restorations are commonly used in both anterior and posterior teeth as an aesthetic restorative material. To serve as a long-term aesthetic restorative material, composite resin should preserve its colour and polish. Discoloration of these composite restorations can be caused by a variety of internal and external factors. Aim:The aim of this study was to assess the marginal discolouration in class 3 composite restoration. Materials and Methods: This was a descriptive study, where all the patients data was collected by reviewing patients records and analysing the data of 86000 patients reported from June 2019 to February 2021 from the Dental Information Archiving Software, Saveetha Dental college and hospitals , Chennai . Data was collected and tabulated ,statistical analysis was done by SPSS – IBM . Results: From the statistical analysis it was found that ,72% of the subjects presented with absence of marginal discolouration and the rest 28% of the subjects presented with marginal discolouration.Marginal discolouration was most commonly seen among 27-30 years of age (40.85%) with equal gender distribution. The most commonly associated tooth was upper central and lateral incisors. Conclusion: A dental office can experience discoloration of a composite restoration. In many circumstances, a second polishing procedure can significantly lighten and brighten the restoration. If not, the palatal outline of the current restoration can be used to do a less complete retreatment. In the retreatment, it's sometimes advisable to perform another color mock-up and choose the lightest alternative.