The present invention provides a novel stable amorphous form of carvedilol dihydrogen phosphate and the process for its preparation that involves reaction of carvedilol base with ortho phosphoric acid in the presence of stabilizer in a suitable solvent or mixture of solvents followed by concentration and isolation. An alternate process for preparation of amorphous form of carvedilol dihydrogen phosphate involves addition of stabiliser to the solution of stable amorphous or crystalline carvedilol dihydrogen phosphate in a suitable solvent or mixture of solvents followed by concentration and isolation. The novel stable amorphous form of carvedilol dihydrogen phosphate is highly stable.