The unique characteristics of marine microbial polysaccharides make them a valuable source of bioactive chemicals that may be employed in a variety of disciplines, including food, feed, anti-tumor, antiviral, antioxidant, and anticoagulant treatments. The strain Advenella kashmirensis 4MA was isolated and identified from sand samples of the Red Sea marine environment using both phenotypic including (morphological biochemical) properties, and genotypic analysis by amplification of its 16S rRNA sequences. The isolate showed the ability to produce EPS with a composition of 40.9.9% sulfate and no uronic acid. The EPS component consists of glucose, xylose, arabinose, and rhamnose in the following molar ratios: 1.0:2.0:4.0:3.0 with molecular weight number-average 4.9×104 g/mol and molecular weight is 5.4×104 g/mol. The obtained EPS was biologically evaluated, and it showed a pronounced antioxidant activity up to 98.97 ± 1.9% at a concentration of 2000 µg/ml after 60 minutes. The IC50 value against the DPPH radical was approximately 500 µg/ml after 15 minutes. While the scavenging activity of H2O2 was 75.91± 2.1 at a concentration of 2000 µg/ml after 60 minutes. The IC50 value for the radical of H2O2 was determined after 15 minutes to be approximately 1500 µg/ml. furthermore, the anticancer activity of EPS was determined towards A-549, HepG-2, HCT-116, PC-3, MCF-7, HEP-2 proliferation and the IC50 values was 940.9±45.3, 485.1 ± 23.5, 841.2 ±34.6, 925.4 ±38.2, 1552 ± 59.4, and 988.3± 49.1 µg/ml respectively. Finally, the EPS showed a good anti-inflammatory with inhibition activity toward LOX and COX2 with IC50 reaching 14.5±0.92µg/ml and 28.6±1.8 µg/ml respectively.