The present invention relates to a bathing composition prepared by the processes of liquid-fermenting medicinal herb comprising 10 to 25 weight% of Zizania latifolia, 10 to 20 weight% of Artemisia capillaries, 5 to 15 weight% of Houttuyniae herba, 1 to 20 weight% of Saururus chinensis Baill, 1 to 15 weight% of Leonuri herba, 1 to 15 weight% of Angelica Gigas root, 1 to 15 weight% of Job's tears, 1 to 10 weight% of Plantago seed and 1 to 10 weight% of Rhododendron brachycarpum, using Bacillus subtilis which is anaerobic, so as to obtain a culture, separating sludge from thus-obtain culture, and drying, sterilizing and grinding the culture. The present invention also relates to a method for preparing the composition.