Abstract: 【Objectives】It will provide basic data and scientific basis for the carbon sink enhancement measures of tropical forests, and the accurate assessment on the contribution of ecological carbon sink in Hainan Island to the goal of carbon neutrality. 【Methods】In this study, the latest data from forest resources surveys and forest plots were used to study the forest ecosystem carbon storage and its variation characteristics in National Park of Hainan Tropical Rainforest (NPHTR) by spatial statistical analysis. 【Results】The results were as follows: the total ecosystem carbon storage of NPHTR was 89.67 Tg, and the carbon storage of vegetation, soil, and litterfall was 39.38, 49.65, and 0.64 Tg. The ratio of the ecosystem was 43.92%, 55.37%, and 0.71%. The ecosystem carbon density of NPHTR was 158.62 Mg/hm², and the carbon density of vegetation, litterfall, and soil were 95.91, 1.55, and 120.91 Mg/hm² respectively. The carbon ecosystem carbon storages of the natural forest and the planted forest were 77.41 and 12.26 Tg, and the ratios were 86.33% and 13.67%. The carbon storage of tropical lowland rainforest and mountain rainforest were the biggest ones of tropical forest, and the ratio is 82.45%. The carbon density of the tropical mountain rainforest (289.52 Mg/hm²) was the biggest one of tropical forests, and the smallest one was in the shrub (81.95 Mg/hm²). The carbon sequestration of tropical forests in NPHTR was 1.84 Tg/a. 【Conclusions】The amount of forest ecosystem carbon storage, carbon density and carbon sequestration NPHTR is bigger than in other ecosystem. In the future, it is important to strengthen the protection of natural forests and ecological restoration of planted forests, to improve the quality of forests, and to increase the carbon sequestration of tropical forest ecosystems.