The previous studies on N. lappaceum L. have shown that it contains certain phytoconstituents such as geraniin, ellagic acid, carotenoids, flavonoids, phenolic and corilagin. 8 Researchers also reported that it possesses several biological activities such as antioxidant, anti-inflammatory, antidiabetic, antibacterial, anticancer, antifungal, antiviral and analgesic property. 9 ABSTRACT Introduction: Diabetes mellitus is a chronic disease that occurs in the majority of people worldwide. The number of cases in many countries has been increasing year by year. In Malaysia, the statistics show that the number of diabetic case in 2019 was 3.6 million and expected to increase in 2025 by 7 million. This disease can develop as a result of oxidative stress production in the body. Nephelium lappaceum was claimed traditionally being used to treat diabetes mellitus. This research is conducted to review the available literature regarding the antioxidant and antidiabetic activities of Nephelium lappaceum extracts and constituent that contributes to this activity. Methods: The studies included in this review have been selected using several databases including Google Scholar, Wiley Online Library, Science Direct and Pubmed. The keywords used in database search were "Nephelium lappaceum" , "antioxidant" and "antidiabetic" and covered the period from 2007 onwards. Results: This review revealed that Nephelium lappaceum extracts have good antioxidant and antidiabetic activities when tested using various methods. These activities are due to the presence of several phytoconstituents in the extract. Conclusions: In conclusion, Nephelium lappaceum possess antioxidant and antidiabetic activities. It has the potential to be developed as an antidiabetic and antioxidant agent which can be used to treat various oxidative stress-related diseases, including diabetes mellitus.