Fungi that selectively remove lignin cause extensive bleaching of leaf litter, which results in the acceleration of litter decomposition. The taxonomic diversity and host specificity of saprotrophic fungi associated with bleached leaf litter were investigated in a subtropical forest in southern Japan. A total of 211 fungal isolates and sporocarps were obtained from bleached portions on leaf litter of 33 plant species on 18 families and were classified into 83 operational taxonomic units (OTUs) at the 97% similarity level of the ITS rDNA sequence. These fungal OTUs belonged to Rhytismataceae and Xylariaceae in the Ascomycota and Marasmiaceae, Mycenaceae, Lachnocladiaceae, and Physalacriaceae in the Basidiomycota. We found that OTUs in Rhytismataceae and Marasmiaceae showed a significantly higher degree of specificity for plant species than simulated networks where partners were associated randomly. In contrast, OTUs in Xylariaceae and Mycenaceae showed no significant specificity for plant species. Such differing degrees of specificity for plant species implied different roles of fungal families in leaf litter decomposition.