In this study antioxidant, antimicrobial and anti-quorum sensing activities of the methanol extracts of 15 wild mushroom species and culture mushrooms (Pleurotus ostreatus) cultivated on four different substrate mediums were investigated. Anti oxidative activity was measured by four different assays. Antimicrobial potential of extracts was tested using agar well diffusion method against Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, Enterococcus faecalis ATCC 29212, Pseudomonas aeruginosa ATCC 27853, Salmonella Typhimurium ATCC 14028, Klebsiella pneumoniae ATCC 13883, Proteus mirabilis ATCC 7002, Listeria monocytogenes ATCC 43251, Candida parapsilosis ATCC 22019 and Candida albicans ATCC 10231. Anti-quorum sensing activity was tested on Chromobacterium violaceum ATCC 12472. Among all mushrooms, Lactarius insulsus had the remarkable results with the highest total phenolic content and antimicrobial effect against C. albicans, P. mirabilis, K. pneumoniae, L. monocytogenes. Three of the cultivated Pleurotus ostreatus mushroom and three wild mushroom extract showed inhibition of the violacein production by C. violaceum. These results revealed the importance of mushrooms as an effective alternative for the prevention and the treatment of many infectious diseases.