Muntingia calabura fruit contains numerous phytochemicals with medicinal value; however, its utilization remains limited due to rapid ripening and poor storability. Fermentation using Saccharomyces cerevisiae is considered a promising approach to extend shelf life and preserve bioactive compounds. This study aimed to evaluate the phytochemical composition and antioxidant activity of fermented extracts from ripe M. calabura fruits. Phytochemical screening, the Folin–Ciocalteu method (for total phenolic content), the aluminum chloride colorimetric method (for total flavonoid content), and the DPPH radical scavenging assay were employed. The fermented product exhibited 8% ethanol, 8.5° Brix, and pH 4.0. The phytochemical constituents detected included saponins, polyphenols, cardiac glycosides, triterpenoids, and alkaloids. The total phenolic content was 95.87 ± 2.00 mg GAE/g, the total flavonoid content was 6.96 ± 0.21 mg QE/g, and antioxidant activity was expressed by an IC₅₀ value of 203.9 ± 1.0 µg/mL. Fermentation of M. calabura fruit with S. cerevisiae effectively preserved, demonstrating strong potential for the development of natural fermented beverages and functional food products derived from this tropical fruit.