There has been exponential demand in the field of medical science on discovering treatment that could address degenerative diseases with minimal contraindication; thus, this study revolved on this premise. The study was conducted to test the extracts of Lato (Caulerpalentillifera), Guso (Eucheumacottonii) and Turtle grass (Thalassiatestudinum) of their anti-diabetic and antioxidant properties. The researcher employed descriptive and experimental research designs with the used of UV-Vis spectrophotometer and kits to analyze their phytochemical constituent. The findings showed that the phytochemical flavonoids were present in the plant extracts. Statistical data showed that the extracts exhibited potential ʆ-amylase and DPPH radical scavenging activity inhibitor in a concentration-dependent manner. It was found that there were significant differences of the percent ʆ-amylase inhibitory activity of selected marine plants extracts and percent DPPH scavenging activity, compared to its positive control treatment, while there were no significant differences on the percent ʆ-amylase inhibitory activity and DPPH scavenging activity potential among three selected marine plants since they were closely similar to each other. Therefore, the results indicated to the potential of the selected marine plant extracts as anti-diabetic agent by inhibition of ʆ-amylase could lead to reduction of blood sugar in a diabetic condition; and with antioxidant properties to scavenge free radicals which caused illness in the human body.