Purification of hyaluronic acid

The present invention relates to a method for purifying a hyaluronic acid or its salt (hereinafter referred to as "hyaluronic acid"). More specifically, the elimination of after removing the ultrafiltration perform a process to small molecular weight hyaluronic acid and the dye for the hyaluronic acid containing broth obtained by microbial fermentation activated carbon, and optionally the addition of gamma-alumina proteins, nucleic acids and endotoxins, such as impurities, and characterized by, the present invention relates to a method for the purification of hyaluronic acid in high purity.