Fungi that remove lignin selectively from leaf litter cause the whitening or bleaching of the litter. Previous studies have demonstrated that fungi in Basidiomycota bleach forest floor materials around their fruiting bodies, leading to faster mineralization of carbon and nitrogen in bleached than in nonbleached materials. In the last 20 years, I have researched the ecology, diversity, and functioning of fungi associated with the bleaching of leaf litter within individual leaves. These studies have shown that not only Basidiomycota (Mycenaceae, Marasmiaceae, and Lachnocladiaceae) but also Ascomycota (Xylariaceae and Rhytismataceae) are capable of bleaching the litter. Species in Rhytismataceae and Marasmiaceae are host-specific and more frequent on a particular tree species, whereas those in Xylariaceae and Mycenaceae are not. Generally, Rhytismataceae, Lachnocladiaceae, and Marasmiaceae exhibited selective lignin decomposition, Mycenaceae exhibited simultaneous decomposition of lignin and other components, and Xylariaceae exhibited selective decomposition of components other than lignin. The area of bleached portions on leaf surfaces was significantly and positively correlated with mean annual temperature of the study sites in tropical, subtropical, and temperate forests in Asia and Australia. The composition of bleaching fungal assemblages on Castanopsis sieboldii leaves was significantly affected by latitude and mean annual temperature of the sites.