The invention relates to an industrial preparation method of hydroxychloroquine sulfate, which comprises heating 4, 7-dichloroquinoline and hydroxychloroquine side chain at refluxing temperature to 120-125 DEG C, allowing reaction to obtain hydroxychloroquine, and reacting with sulfuric acid to obtain hydroxychloroquine sulfate. The method can obtain high-purity hydroxychloroquine sulfate with single impurity less than or equal to 0.1% and purity higher than or equal to 99.5%; and has less preparation procedures, simple process, high product yield, good quality, low environmental pollution, no use of highly toxic solvent, and is easy for industrial production.