Understanding litterfall dynamics is crucial for assessing nutrient cycling and ecological processes within forest ecosystems. This study examines seasonal litterfall patterns across three major Cambodian forest types, Deciduous, Semi-evergreen, and Evergreen forests, over a three-year period (2022-2024). The study site was the Khun Ream Forest Research Center (90 m a.s.l.) in Siem Reap, Cambodia, with an annual rainfall of 1,358 mm and a mean temperature of 27.7°C. We collected monthly litter using 25 litter traps (0.49-0.50 m² each), which were arranged in a 10-m grid at the center area of 1-ha plot in each forest, and oven-dried litter for 72 h at 80°C. After separating the litter into leaves, twigs, reproductive parts (flower, fruits, and seeds), and others, we weighed the dry weights of each component to the nearest 0.01 g. Results showed that total annual litter production varied among forest types, with Deciduous forests producing 5.8 Mg/ha, Semi-Evergreen forests 7.2 Mg/ha, and Evergreen forests 8.5 Mg/ha. Seasonal variations were distinct, with peak litterfall occurring around at the end of dry season. Litter composition analysis revealed that leaves constituted 60-75%, twigs 15-25%, and reproductive parts 5-15% of total litterfall. These findings provide key insights into forest nutrient cycling and contribute to improve conservation and management strategies for Cambodia’s forest ecosystems.