Objective:To explore the relationship between changes in cranio-cervical extensor muscles and sleep quality of patients with chronic tension-type headache(CTTH).Methods:A total of 10 CTTH patients(CTTH group)and 10 healthy individuals(control group)were collected.Morphological changes in the cranio-cervical extensor muscles were detected using MRI.Sleep quality was assessed using the Pittsburgh Sleep Quality Index(PSQI).Results:There were significant differences in subjective sleep quality score and daytime dysfunction score between the two groups(P=0.039,0.001).No correlations were found between subjective sleep quality score or daytime dysfunction score and the relative cross-sectional area of cranio-cervical extensor muscles(all P>0.05).The comprehensive sleep quality score in the CTTH group was negatively associated with the relative cross-sectional area of rectus capitis posterior minor(right,r=-0.705,P=0.023;left,r=-0.585,P=0.035).Conclusions:CTTH may effect the sleep quality in subjective sleep quality and daytime dysfunction,and the atrophy degree of rectus capitis posterior minor is related to sleep quality of CTTH patients,the more severe atrophy,the worse the sleep quality.