This study investigated the composition and spatiotemporal dynamics of litterfall at the community scale, on the basis of 144 square traps distributed uniformly in a 5.76 hm² permanent plot located in the deciduous broad-leaved forest of Mopan Mountain. The litterfall samples were collected monthly from April to November in 2006. The results showed that the annual litter production was 3039.6 kg/hm². The proportion of leaves (2499.2 kg/hm²) was 82.22%, and that of branches was 9.92%. The combination of flowers, fruits and barks was less than 5%. The leaf litters were from 42 tree species, accounting for 91.30% of the total number (46) of the tree species in the plot. The main sources of leaf litterfall were Fraxinus rhynchophylla, Juglans mandshurica and Quercus mongolica, accounting for 82.97% of the overall amount. The litterfall exhibited evident spatial heterogeneity, with 200-400g litters in 99 traps and >600g litters in 2 traps. Some traps collected as many as 19 species, but most (29 traps) did only 12 species. A single-peaked curve described the dynamic of monthly litterfall, and 69.78% of litterfall occurred in September and October. Leaf litterfall peaked in autumn and exhibited the same temporal trend as the overall litterfall. However, different species peaked in a different manner, with Juglans mandshurica at August and September, Ulmus japonica at September and October, Acer mono at October, and Quercus mongolica at October and November, respectively.