#$%^&*AU2017101408A420171123.pdf#####ABSTRACT The present invention provides a synthetic method of Cyclo(His-Pro), comprising steps of: preparing His-Pro dipeptide methyl ester with protected amino group from histidine and proline, wherein one of histidine and proline is in the form of methyl ester hydrochloride and the other is in the form of protected amino group; deprotecting and cyclizing the His-Pro dipeptide methyl ester with protected amino group to produce Cyclo(His-Pro).