ABSTRACT: The present research was performed to investigate the effects of the extracts of four marine sponges on some biochemical parameters including antioxidant and three different carbohydrate hydrolyzing enzymes: alpha-Amylase, beta-galactosidase and alpha-glucosidase. The sponges were collected from Red Sea at Egyptian coasts, and taxonomically belonged to the genus of Smenospongia (SP1), Callyspongia (SP2), Niphates (SP3) and Stylissa (SP4), respectively. The sponges extracts exhibited diverse inhibitory effects on oxidative stress indices and carbohydrate hydrolyzing enzymes in linear relationships to some extent with concentration of inhibitors (dose dependant). The extracts of sponges (3, 1 and 2) showed, respectively, potent reducing power. Chemical characterization of sponge 1 recognized the existence of di-isobutyl phthalate (1), di-nbutyl phthalate (2), linoleic acid (3), beta-sitosterol (4) and cholesterol (5), while sponge 3 produced bis-[2-ethyl]-hexyl-phthylester (6) and triglyceride fatty acid ester (7).