Mushrooms are among the natural products that are widely used in the treatment of diseases. In our study, the biological activities of Candolleomyces candolleanus (Fr.) D. Wacht. & A. Melzer were determined. Within the scope of the study, ethanol and methanol extracts of the basidiomata of the mushroom were obtained. Total antioxidant, total oxidant, and oxidative stress values of the mushroom were determined using Rel Assay kits. Its antimicrobial activity was tested against standard bacterial and fungal strains by agar dilution method. Antiproliferative activity was measured against A549 lung cancer cell line by MTT assay. Element contents were determined using atomic absorption spectrometry. According to the findings, the TAS value of the mushroom was determined as 5.547 ± 0.173, the TOS value as 8.572 ± 0.217 and the OSI value as 0.155 ± 0.001. It was determined that the mushroom extract was effective at 25-400 μg/mL concentrations. Element contents were determined to be at normal levels. The antiproliferative activity of the extracts showed strong effects depending on the concentration increase. As a result, it was determined that the biological activities of the extracts of C. candolleanus were high.