Sleep is a natural phenomenon which is known as one of human physiological needs and is one of the important elements in the circadian cycle which is followed by the restoration of physiological and mental power. As people spend one third of their lives in sleep, sleep disorders can, for different reasons, disrupt the normal order of normal physiological sleep and leads to some problems such as fatigue, lassitude, irritability, reduction of physical and mental abilities, reduction of attention and concentration, headache and etc. Thus the present study aimed to investigate the prevalence of sleep disorders among medical students of the Medical Sciences Faculty of Islamic Azad University, Shahroud branch. The present study was carried out on 42 medical students who were chosen by simple random sampling method and did not have any known mental disease or significant medical and physical problems and disability. Students answered the Pittsburgh Sleep Quality Index (PSQI), and then the data was transferred to SPSS-v20 software and was analyzed. In this investigation 88.1% (37 students) were females and their average age was 22.666±0.901. Among these, 28.6% (12 students) were healthy, 64.3% (27 students) had borderline symptoms and the others had symptoms of the disease. Sleep is one of human’s physiological and basic needs and sleep disorder threatens human health; so paying attention to sleep health has an important role in providing the mental and physical health of the society population.