Plasma concentration of calcitonin gene-related peptide (CGRP) and substance P (SP) were measured by radio-immuno assay (RIA) in 49 migraine patients during migraine attack (n= 26) or remitent period and in 20 blood donors without headsches. Blnd was taken both from external jugular vein (EJV) and from cubital vein (CV) in the same person.Twelve petients during migraine attack were tteated with sumatriptu. The therapeutic effect was correlated with the changds in plasma concentration of CGRP and SP. The results showed that: (1) There is a significant increase of plasm CGRP and SP concentration in migraine attack patients in blnd taken from EJV but not ftom CV; (2) The EJV plasma concentration of CGRP and SP returned to normal level when the attuck was over; (3)Sumatriptun showed a rapid therapeutic efficacy in Chinese migraine potients without significant side effects.