Abstract: Forty three species, 2 varieties of the genus Agaricus are reported. Among them, Agaricus squarrosus Li. sp. nov. , A. dimorphosquamatus Li. sp. nov. and A. lepiotiformis Li. sp. nov. are new to science, and sixteen species are new records to China. A key of all taxa has been provided. All the specimens cited above deposi-ted in the Mycological Herbarium of Institute of Microbiology, Academia Sinica, Beijing (HMAS) .

Key words: Agaricus, A. squarrosus