The present invention relates to a composition for dispersing or hydrating mucus, which comprises poly-gamma-glutamic acid, a biocompatible natural polymer, and more particularly, to a composition for treating mucus hypersecretory disease, which comprises poly-gamma-glutamic acid or poly-gamma-glutamic acid nanogels. The composition according to the present invention is effective in treating mucus-related diseases by effectively dispersing and hydrating mucus which is excessively secreted in vivo and highly sticky.
