In this study, we investigated the phenolic profile, metal concentrations, and antioxidant and antimicrobial activities of edible mushrooms collected from Sinop, Turkey: Amanita caesarea, Boletus edulis, Grifola frondosa, Hydnum repandum, Lactarius deliciosus, L. piperatus, L. volemus, Laetiporus sulphureus, Pleurotus ostreatus, and Ramaria flava. The mycochemical contents of R. flava, L. sulphureus, A. caesarea, L. deliciosus, and B. edulis were high. The cobalt (Co), cadmium (Cd), nickel (Ni), and lead (Pb) contents of mushrooms were between < 0.54 and 8.97 ppm. L. deliciosus had effective total antioxidant activity (7990 μmol α-tocopherol eq./g), ABTS·+ (2,2'-azino-bis-(3-ethylbenzthiazoline-6-sulphonic acid)) scavenging activity scavenging activity (EC50:7.87 μg/mL), and free-radical scavenging activity (EC50: 0.018 μg/mL) due to high levels of phenol, flavonoid, β-carotene, and lycopene. B. edulis demonstrated strong reducing power (A0.5: 11.89 μg/mL), inhibition of linoleic acid peroxidation (EC50:0.0016 μg/mL), and H2O2 scavenging activity (EC50: 0.28 μg/mL). A. caesarea and R. flava showed the best metal chelating activity (EC50:44.31 μg/mL) and superoxide anion scavenging activity (EC50:0.18 μg/mL), respectively. Inhibition zone values of A. caesarea extract were detected between 8.1 and 27.1 mm for B. cereus. Our results show that mushrooms are promising dietary sources for natural prevention of many infectious diseases and that they act as antioxidant agents.