THE INVENTION PROVIDES AN AMINE SALT OF A CARBOSTYRIL DERIVATIVE FORMED FROM A CARBOSTYRIL DERIVATIVE REPRESENTED BY THE FORMULA (1) [WHEREIN R IS A HALOGEN ATOM; THE SUBSTITUTED POSITION OF THE SIDE CHAIN IS 3- OR 4-POSITION IN THE CARBOSTYRIL SKELETON; AND THE BONDING BETWEEN 3- AND 4-POSITIONS OF THE CARBOSTYRIL SKELETON IS A SINGLE BOND OR A DOUBLE H BOND] AND AN AMINE; AND THE INVENTION IS USEFUL AS DRUGS FOR TREATING VARIOUS DISEASES, ESPECIALLY AS AQUEOUS FORMULATIONS DUE TO THE SUPERIOR WATER SOLUBILITY AND THE SUPERIOR PHARMACOLOGIC EFFECTS.