The present invention relates to a macrolide derivative as well as preparation and use thereof. The macrolide derivative of the present invention, i.e., a hydrate of erythromycin salts, has a molecular formula of C 37 H 67 NO 13 ·A·nH 2 O, n=1.0-11.0, in which A is an organic acid or an organic acids, selected from lactobionic acid, thiocyanic acid, maleic acid, fumaric acid, thiocyanic acid, acetic acid, methanesulfonic acid, benzenesulfonic acid, nicotinic acid, lactic acid, citric acid, tartaric acid, aspartic acid, glutamic acid and phosphoric acid, the hydrate has good water solubility and better storage stability, which is suitable for the manufacture of a medicament for the treatment and prophylaxis of infectious diseases in human or animal caused by Gram-positive or negative bacteria.
