Jianfengling tropical mountain rainforest in Hainan is one of the typical tropical forest ecosystems. Its long term climatic dynamics is important for global change research. Some climatic factors, such as radiation, moisture and wind, were analyzed in light of the meteorological data recorded for the area by the Opened Research Station of Jianfengling Tropical Forest Ecosystem. The present study critically analyzed the dynamic characteristics of these climatic factors over a period of 26 years. The results showed that, the precipitation, mean relative humidity and mean vapor pressure on annual basis have been rising in the past 26 years over the Jianfengling forest. Annual mean vapor pressure increased significantly and annual sunshine hours, evaporation and mean wind speed also exhibited an ascending trend, though an obvious decrease in the wind speed was recorded. While the yearly changes of monthly precipitation and evaporation fluctuatecd irregularly, the monthly precipitation in October and evaporation in September showed a decreasing trend. Climate warming effect reveals that under global change, there was climate warming process occurring in the Jianfengling tropical mountain rainforest.