Decomposition process is one of the major processes for understanding forest carbon cycle. We measured weight loss, mineralization and fragmentation rate of leaf litter of evergreen species in Fujisawa experimental forest, in Fujisawa Japan. We collected live leaves of Ligustrum japonicum, Lithocarpus edulis, Myrica rubra, Castanopsis sieboldii from living trees in March 2011. We tagged number tape, measured leaf area and dry weight. We set the sample on the forest floor without "litter bag" from April to December, 2011. We collected 10 samples from each species, measured respiration rate, leaf area and dry weight. We used the relationships between respiration rate, temperature and water content to estimate the total mineralization rate of each species during the experimental period. We also measured weight loss rate from weighing dry weight changes. We estimated fragmentation rate as the difference between dry weight loss and mineralization rate. These rates were different among these species according to the morphological characteristics which controlled moisture content of the leaf litter.