Seaweed has been known to possess beneficial effects forhuman health due to the presence of functional bioactive components. Then-butanol and ethyl acetate extracts ofDictyota dichotomashowed ash (31.78%), crude fat (18.93%), crude protein (14.5%), and carbohydrate (12.35%) contents. About 19 compounds were identified in then-butanol extract, primarily undecane, cetylic acid, hexadecenoic acid,Z-11-, lageracetal, dodecane, and tridecane, whereas 25 compounds were identified in the ethyl acetate extract, mainly tetradecanoic, hexadecenoic acid,Z-11-, undecane, and myristic acid. FT-IR spectroscopy confirmed the presence of carboxylic acid, phenols, aromatics, ethers, amides, sulfonates, and ketones. Moreover, total phenolic contents (TPC) and total flavonoid contents (TFC) in ethyl acetate extract were 2.56 and 2.51 mg GAE/g and inn-butanol extract were 2.11 and 2.25 mg QE/g, respectively. Ethyl acetate andn-butanol extracts at a high concentration of 100 mg mL−1showed 66.64 and 56.56 % inhibition of DPPH, respectively. Antimicrobial activity revealed thatCandida albicanswas the most susceptible microorganism, followed byBacillus subtilis, Staphylococcus aureus, andEscherichia coli, whereasPseudomonas aeruginosashowed the least inhibition at all concentrations. The in vivo hypoglycemic study revealed that both extracts exhibited concentration-dependent hypoglycemic activities. In conclusion, this macroalgae exhibited antioxidant, antimicrobial, and hypoglycemic potentials.