Preparation method of erlotinib hydrochloride crystal form A

The invention specifically relates to a preparation method of an erlotinib hydrochloride crystal form A. The preparation method comprises the following steps of: mixing erlotinib hydrochloride free alkaline monomer with an organic solvent; and dropwise adding a non-ether hydrogen chloride solution or a hydrogen chloride solution for reacting to obtain the erlotinib hydrochloride crystal form A under low-temperature reaction condition. The preparation method of the erlotinib hydrochloride crystal form A is incapable of affecting industrial production due to weather temperature changes, simple and convenient to operate, very good in safety, high in stability, good in repeatability and more suitable for the industrial production of the erlotinib hydrochloride.