In this study, we analyzed the contents of different bioactive compounds, including those with antioxidant activity, in selected mushroom species. Analysis of DPPH radical-scavenging activity revealed that Agaricus bisporus(‘A15’) had the highest antioxidant efficacy at 33.1 μg/mL, followed by Lentinula edodes and Pleurotus ostreatus, for which we also recorded high values. The results of nitrite-scavenging activity analysis revealed L. edodesto have the highest value at 15.8 μg/mL, with A. bisporus, P. ostreatus, and Wolfiporia extensaalso showing relatively good results. Furthermore, our analysis of total polyphenol contents indicated that A. bisporus had the highest content at 13.7 μg/mL, with L. edodesand Flammulina filiformis similarly having high levels, whereas W. extensa was established to contain the highest levels of β-glucan at 32.6 μg/mL, followed by L, edodes and P; ostreatus, which were also found to have significantly high values. These findings indicate that the antioxidant and nitrite-scavenging capacities and polyphenol and β-glucan contents differ according to fungal species. Among the evaluated species, given its high contents of a range of bioactive compounds, A. bisporus was assessed to be a suitable candidate for functional food development, Our findings in this study will provide essential basic data for the development of functional foods using edible mushroom species.