Objective：To explore clinical features of chronic migraine（CM） and to test the International Classification of Headache Disorders-Ⅲ，beta version（ICHD-Ⅲ beta） and Expert Opinion criteria（EOc） in practice. Methods：Demographic characteristics and clinic features of CM patients in neurology outpatient department of the First Affiliated Hospital of Chongqing Medical University from June 2014 to June 2016 were retrospectively analyzed. CM diagnostic criteria according to ICHD-Ⅲ beta and EOc were evaluated. Results：A total of 236 CM patients were included：165 patients（69.9%） were concurrent with medication overuse，just 2 patients （0.8%） used triptans and none used ergotamines. The most common migraine subtype was migraine without aura（MO，70.3%），followed by probable migraine（PM，26.3%） and migraine with aura（MA，3.4%）. All 236 patients met the EOc criteria and only 167 patients（70.8%） met ICHD-Ⅲ beta for CM. For the 69 patients who met EOc but not met ICHD-Ⅲ beta，62 had atypical migraine attacks，which was consistent with PM，and another 7 had typical migraine attacks but less than a total history of 5 attacks. Conclusion：CM patients are often in combination with medication overuse，however，migraine-specific medications including triptans and ergo－tamines，are used infrequently. According to the situation of Chinese CM patients，the EOc is more suitable and may be more appro－priate in the clinical work.