Abstract:The production dynamic, main chemical components and its storage of litter-fall in two major forest types in the Jianfengling mountains region in Hainan Island were studied in the present article.The mean annul total dry weight of litter-fall in the tropical mountain rain forest (alt. 850m) is up to 7.7t/ha containing branches 21.3%, leaves 70.7%, and flowers and other mixed-matter only 8.0%; while in the semideciduous monsoon forest (alt. 200m) it is 9.7t/ha, containing 17.5%, 76.4% and. 6.1% of these things respectively. The seasonal change patterns of falling in both types are similar, and the maximum quantity of litter-fall occursin March-April (the driest months) and the minimum in December-January. The change of litter-fall depends on that of the month.The order of the chemical components of litter-fall in these two forest types tends to be Ca>Si>K>Mg>Al>P>Fe>Na, the total amount of elements in the semi-deciduous monsoon forest is greater than that in mountain rain forest. About 70-86% of the contents of chemical elements in both types were rich in the leaves.The amount of the chemical elemtnts of the litter-fall returning back to the soil in the semi-deciduous monsoon forest is greater than that of mountain rain forest.