The invention provides a method for refining erythromycin thiocyanate, which comprises the following steps: (1) fetching erythromycin thiocyanate crude product, dissolving in a solvent, treating with alkali, removing insoluble substances, adding thiocyanate, adding acid for adjusting pH to 5.5-8.3; (2) precipitating solid, washing, drying and obtaining the erythromycin thiocyanate finished product; wherein, the solvent in the step (1) is methanol, ethanol or isopropanol; Or, the solvent is a mixed solvent containing more than two ingredients among methanol, ethanol, isopropanol, water, acetone, dichloromethane, ethyl acetate and butyl acetate; in the mixed solvent, the contents of the methanol, ethanol or isopropanol are above 30% w / w. The invention also provides a preparation method of erythromycin thiocyanate. The invention overcomes the technology prejudice that the mixing and dissolving of solvent and water can not reduce the erythromycin impurity, and not only the purity and the yield of the erythromycin thiocyanate finished product are not reduced, but also the solvent cost is substantially saved and the technology step is simplified.