In case of leather objects, degradation usually occurs by a combination of factors such as temperature and relative humidity, light and insect and fungi.Because chemical composition differs on the types of leather materials, leather objects affect differently even in the same environment.According to UV degradation, the overall color and gloss difference appeared severe in turn of the cowskin, sheepskin and pigskin specimens.In addition, despite short-term period of RH degradation, leather materials showed stable result on high RH circumstances.Nevertheless, if the leather sustained for a long time on the high RH, the environment can be the cause of mold or microorganisms.This study is to understand the leather objects and the future conservation and then to establish the conservational management of leather object for the future.