Objective To investigate the relationship between sleep disorders and cognitive function in the urban population aged over 60 in Shijiazhuang， Hebei Province. Methods A questionnaire survey was conducted in the elderly aged over 60 in the urban communities of Shijiazhuang selected by cluster randomized sampling method from 2010 to 2011. According to the total score of Pittsburgh Sleep Quality Index（ PSQI）， the elderly were divided into sleep disorder group and no sleep disorder group. According to the scores of the first and the second entry in the fifth self-assessment item， they were further divided into difficulty falling asleep group， easy to wake up or wake up early group and no sleep disorders group. The cognitive function was assessed by the Mini-mental State Examination（ MMSE） and the Montreal Cognitive Assessment Scale（ MoCA）， and the relationship between sleep disorders and cognitive function was analyzed. Results There were a total of 103 cases completed and effective questionnaires. There were no significant differences in gender， age， marital status， living style and years of education between the two groups（ P＞ 0.05）. After 5 years of follow-up， the cognitive function of the sleep disorder group was significantly lower than that of the baseline data（ P＜ 0.05）. The decrease of cognitive function of the difficulty falling asleep group was significant compared with the other groups（ P＜0.05）. It showed no impact on cognitive function in the easy to wake up or wake up early group（ P＞ 0.05）. Conclusions Sleep disorder in the elderly， especially difficulty falling asleep， may be the influencing factor of cognitive function.