The phenolic content (TPC) and flavonoids (TFC) of the methanol (MeOH) extract of the edible mushroom species 'Ramaria flava' in the native flora of Amanos Mountains were 89.0 and 0.97 mg/kg, respectively. beta-carotene content (TCC) (0.47 mg 100/mL) was higher than that of the lycopene (TLC) (0.19 mg/100 mL). Two-fold dilutions ranging from 1.25 to 5.0 mg/mL of the extract were used for antioxidant assays. The most significant activities were 94.17% for DPPH (2-diphenyl-1-picrylhydrazyl), 64.25% for NO (nitric oxide) scavenging, 2.43 Abs for reducing power (RP) and 1.94 Fe+2 mmol/L for Ferric-reducing antioxidant power (FRAP) assays at the upper concentration, respectively. The most prominent result for hydrogen peroxide (H2O2) scavenging assay at the following concentrations; 0.0156 to 0.125 mg/mL was 71.68% at 0.125 mg/mL. In the bioherbicidal assay, MeOH extract at 25 mg/mL inhibited the germination (16%), radicle growth (44%), plumule growth (52%), total chlorophyll a and b (78 and 88%), and carotenoid (70%) of Cucumis sativus. To conclude, FRAP, NO, and H2O2 scavenging activities of the MeOH extract of R. flava is the first report.