Abstract: This study aimed to investigate the optimal extraction conditions for phenolic compounds from Floccularia luteovirens and to analyze their antioxidant and hypoglycemic activities. The extraction process for phenolic compounds from Floccularia luteovirens was optimized using response surface methodology, and their in vitro antioxidant and hypoglycemic activities were investigated. The optimal extraction conditions for phenolic compounds were found to be an ethanol concentration of 48.19%, a solid-to-liquid ratio of 1:38 g/mL, and an ultrasound time of 35.70 minutes, resulting in a yield of 7.74±0.24 mg/g. The IC₅₀ for DPPH radical scavenging was 43.85 μg/mL, the ABTS⁺ scavenging capacity was 7.81 mmol/g Trolox, and the FRAP ferric ion reduction capacity was 1.58 mmol/g FeSO₄. In in vitro hypoglycemic assays, the phenolic compounds from Floccularia luteovirens exhibited an IC₅₀ of 2.79 mg/mL for α-amylase inhibition and an IC₅₀ of 9.85 mg/mL for α-glucosidase inhibition. In conclusion, the phenolic compounds from Floccularia luteovirens demonstrate excellent antioxidant and hypoglycemic activities, indicating their strong potential for development.