Recent research reported inhibitory effects of Eriobotrya japonica leaf extracts on DPPH free radicals and α-amylase, α glucosidase, and lipase enzymes. These enzymes were linked to the etiology of diabetes mellitus, obesity, and oxidative stress. The current study is aimed at determining the phytocontents of E. japonica aqueous extract leaves and exploring their potential antioxidant, anti-α-amylase, anti-α-glucosidase, and antilipase activity using reference phytochemical and biochemical assays. The phytochemical tests on the E. japonica aqueous extract confirmed the presence of alkaloids, glycosides, tannins, saponins, phytosteroids, carbohydrates, and phenols. The total phenol and tannin contents of the E. japonica aqueous extract were 21 64 ±089mg of GAE/g and 172±1mg of CAE/g, respectively. E. japonica aqueous extract had inhibitory effects on DPPH free radicals (IC50 of 77±311μg/mL) and α-amylase (IC50 =141±035μg/mL) compared with Trolox and acarbose (63±012 and 2818±122μg/mL, respectively). Moreover, E. japonica aqueous extract inhibited α-glucosidase (IC50 =3981±074 vs. 3715±033μg/mL inhibition by acarbose) and lipase (IC50 =3162±087 vs. 123±033μg/mL inhibition by orlistat). In conclusion, the current results suggest that E. japonica aqueous extract possesses strong antioxidant, anti-α-glucosidase, anti-α-amylase, and antilipase activities with potential applications in the treatment and prevention of obesity, diabetes mellitus, and oxidative stress.