A total of 38 fungal taxa were identified on senescent untreated and autoclaved Castanopsis fissa leaves during a 4-month study period. Seventy-six percent of the fungal genera found in this survey have not previously been recorded from Castanopsis. Frequency and time of occurrence of fungal taxa occurring on untreated senescent leaves were clustered into four groups when analyzed by cluster analysis, suggesting the replacement of microfungi in stages of succession on naturally senescent leaves. Autoclaved leaves revealed significantly different fungal communities, with only 26% of overlap with the natural ones and no clear patterns of replacement of fungal communities. Factors regulating the rates of decomposition are also discussed.