The present study aimed to comprehensively assess the bioactive compounds, antioxidant, anti-inflammatory, and anti-diabetic potential of hydro-methanolic extracts derived from naturally grown Noni fruits in Sri Lanka through colorimetric assays. The extraction process involved mixing one gram of fresh fruit flesh samples with 8 mL of 80% methanol, followed by vortexing and centrifugation, after which the resulting extracts underwent filtration and were subsequently utilized in multiple assays. The total phenolics content and total flavonoid content were estimated as 198.60 ± 2.48 μmol gallic acid equivalence/g of fresh weight and 9.19 ± 0.48 μmol rutin equivalence/g fresh weight, respectively. Furthermore, the extract demonstrated IC50 values of 35.87 ± 0.48 µg/ml in the DPPH radical scavenging assay, 33.96 ± 0.30 µg/ml in the phosphomolybdenum assay, and 6.91 ± 0.24 µg/ml in the singlet O2 Inhibition assay. Additionally, the study explored the extract's anti-inflammatory properties, with the nitric oxide inhibition assay exhibiting a value of 73.40 ± 1.20 µg/ml. The membrane lysis assays yielded IC50 values of 9.40 ± 0.80 µg/ml, 4.81 ± 0.21 µg/ml, and 9.12 ± 0.89 µg/ml for the heat-induced hemolysis, protein denaturation inhibition assay, and protease inhibitory assay, respectively. Furthermore, the antidiabetic assays conducted on the hydro-methanolic extractions revealed an α-amylase inhibitory assay value of 13.40 ± 0.20 µg/ml and an α-glucosidase inhibitory assay value of 6.92 ± 0.34 µg/ml. These findings suggest that naturally grown Noni fruits in Sri Lanka possess significant antioxidant, anti-inflammatory, and anti-diabetic potential, highlighting their potential application in functional foods and nutraceuticals.