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Marine sponges which are known to own multiple functional properties have created significant interest among the researchers due to their biological activities and impending application in different industries .The aim of this study was to obtained bioactive components of sponges. Gelliodes carnosa sponge was collected from Nay Band Bay (Persian Gulf waters) and antimicrobial activities of crude extracts were explored by calculation of Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) in media supplement with different concentrations of extract solutions. Seven extracts of sponge with solvents of different polarity (E1: Ethanol, E2: Methanol, E3: Acetone, E4: Ethyl acetate, E5: Chloroform, E6: Mixed (Ethanol: Ethyl acetate: Methanol 1:2:1), E7: Distilled water) were evaluated through disc diffusion assay. Different extracts were inhibited the growth of bacteria (70%) more frequently compared to fungal strains (26%). Gram-negative bacteria were more sensitive (72%) to many extract compared to Gram-positive bacteria (65%). Considerable antibacterial activity was exhibited by E6 against Bacillus subtilis (MIC: 203 µg/ml), Klebsiella pneumonia (MIC: 203 µg/ml), Escherichia coli (MIC: 407 µg/ml) and Fusarium solani (MIC: 500 µg/ml). Strong antifungal activity was obtained by E4 against Fusarium sp.2, Fusarium sp.1, F. solani and Saprolegnia parasitica (MIC: 500µg/ml). This is the first report of antimicrobial and antifungal activities of G. carnosa extracts.