Seed dispersal spectra of woody taxa and seed size distribution of zoochorous woody taxa were studied in different forest types in Japan (Shirakami Sanchi, Mount Fuji, Nara, Shiroyama, and Yakushima Island) and China (Mount Emei, Longqi Mountain, Meili Snow Mountains, Xishuangbanna, and Jianfengling) to trace shifts in these fruit traits along the latitudinal and altitudinal gradients. The forest types studied are broad-leaved evergreen, mixed mesophytic, broad-leaved deciduous, subhumid sclerophyllous, and different tropical forests. Clear relationships are evident between dispersal mode, seed size class distributions, and the various forest types. The distribution of dispersal modes and of seed size classes differs significantly between the vegetation types. Animal dispersal is more important in broad-leaved evergreen and tropical moist forests, whereas wind dispersal is more common in subhumid sclerophyllous, tropical monsoon, and deciduous forest types. Large seeds (>15 mm) of fleshy-fruited taxa are predominant in tropical moist forests but almost absent in the other forest types. Large seeds of nonfleshy animal-dispersed taxa, however, are found across all forest types. Abiotic dispersal mechanisms are consistently low across the forest types. This study is designed as a source for the future evaluation of the Paleogene–Neogene plant record and will contribute to a more comprehensive understanding of ecosystem evolution and dynamics.