Betahistine is a new type of histamine H1 receptor weak agonist. It has the function of expanding capillaries, relaxing the anterior capillary sphincter, and increasing the blood flow of the anterior capillary microcirculation. It is mainly used for the treatment of Meniere's syndrome(inner ear vertigo), vascular headache and cerebral arteriosclerosis. It can also be used for the treatment of acute ischemic cerebrovascular diseases. Related substance research is one of the key items in drug quality research, and its content is a direct indicator of drug purity. This article reports five synthetic methods of betahistine related substances, hoping to provide reference for the pharmacol. research of betahistine and related substances.