In order to enhance water solubility, ketoprofen was made as lysine salt, such as acetylsalicylic acid lysine salt, ibuprofen lysine salt and amino acid salt of phenylbutazone. The purpose of this study was to make a comparison between ketoprofen lysine salt in aspects of analgesic, anti-inflammatory, and antipyretic effect. The experimental results were summerized as followings. 1. Ketoprofen lysinate was composed of one molecule of ketoprofen and one molecule of lysine. The product was water soluble and melting point was $92^{circ}C{sim}94^{circ}C$. 2. Ketoprofen lysinate showed about 2 times stronger analgesic effect than that of ketoprofen while no difference in antipyretic effect was observed. 3. $LD_{50}$ of ketoprofen lysinate was higher than that of ketoprofen, suggesting ketoprofen lysinate as safer drug. 4. Blood concentration of ketoprofen lysinate was $156{mu}g/ml$ while the concentration of ketoprofen was $116{mu}g/ml$ in 30 min., suggesting long acting as well as high blood concentration.