Here, we present the results of studies of Japanese Hebeloma collections. The four species described by Imai as Hebeloma (H. fimicola, H. helvolescens, H. humosum, and H. tomoeae) are not from the genus Hebeloma, but are members of Agrocybe, Homophron, or Pholiota. Recombinations are made. Hebelomacrustuliniforme f. microspermum, described by Hongo, is a synonym of H. nanum. Three species of Hebeloma are described as new to science, all currently known only from Japan. Two of these species, H. asperosporum and H. cinnamomeum, are members of H. sect. Denudata while the third species H. citrisporum belongs to H. sect. Velutipes. Japanese records of H. cavipes, H. eburneum, H. hygrophilum, H. subtortum, and H. velutipes are validated. In total, fifteen species of Hebeloma are confirmed from Japan; this is compared with previous checklists.