Sponge associated marine microbes recognised as potential candidate for screening and isolation of bioactive compounds for range of disease. In this study totally 14 heterotrophic and morphologically different bacterial colonies were isolated from marine sponge Spirastrella inconstans. The isolated strains were cultured in marine broth and extracted with ethyl acetate for screening of antimicrobial activity against a panel of human pathogens. The pigmented strains showed moderate activity of which strain MB13 showed inhibitory activity against all the tested pathogens was identified as Pseudoalteromonas piscicida using 16s rRNA sequencing. Two of non-pigmented strains also showed week antimicrobial activity.