The prevalence of migraine was investigated in all provinces, municipalities and autonomous regions (except Taiwan) of the People's Republic of China. Random sampling from provincial capitals and from rural areas according to demonstration were used. Among a total screened population of 3,837,597 persons, there were 37,808 cases of migraine. The morbidity and the annual incidence rate were 985.2/100,000 and 79.7/100,000, respectively. The male/female ratio was 1:4. Inland plateaus were higher morbidity areas (more than 1,500/100,000) and coastal provinces and cities were lower morbidity areas (less than 400/100,000). The incidence rate was higher in spring in the south, while it was higher in summer in the north. The incidence rate was higher in hot and damp climate. The morbidity under 14 years old in China was significantly lower than those in overseas reports.