To study the environmental adaptability of OLED displays in tropical rainforest, OLED displays are placed into the storeroom of experimental station in Xishuangbanna, and they are observed and tested regularly. After one-year-exposure, the surface of OLED displays appears pinhole, black point, and obscission. In addition, the area of luminescence and brightness were reduced. Investigation revealed: the sealing of OLED displays is destroyed in tropical rainforest, subjected to the long term alternating stress caused by temperature and humidity, thus led to the failure of OLED with oxygen and moisture in the interior of displays. Therefore, an improved sealing is the key to the service life of OLED displays in tropical rainforest.