SEVEN common marine-derived fungi were isolated from different collection sites distributed in Eastern and Western harbor of Alexandria, Egypt. The most promising marine-derived fungusproducing exopolysaccharide (EPS) was Penicillium commune (KP942881.1) which was identified according to microscopic morphological features and confirmed genetically by 18S rRNA gene. The results of the optimizing conditions for EPS production from marine-derived P. commune showed that 40 mg/ml of sucrose, 20 mg/ml of peptone, pH 5 and 3 cm discs of inoculum size and incubation at 30oC, for 9 days were the optimal conditions with using static condition for all factors. Three main spectroscopic analyses (FTIR, 1H NMR and HPLC) were employed to characterize the EPS extracted from marine-derived P. commune.1HNMR analysis of EPS exhibited the presence of β-galatopyranosyl. The HPLC chromatography showed that the EPS consist of two peaks; raffinose and rhamnose. EPS showed antiproliferative activity at dose 10 mg/ml where the percentage inhibition of tumor viability cells of colon was 85%. In breast cell (Mcf-7), EPS inhibited 87% of the tumor cells at dose 10 mg/ml and also the antiviral activity of EPS of P. commune exhibited 22.8% inhibition.