Sleeping is an unintentional habit of creatures that involve all organisms, including plants, animals and human being. On the other hand, sleeping and dreaming are closely interrelated. It should be considered that, sleeping and dreaming resemble shadows that chasing objects. Sleeping is so important that a division of relationship between human and the God takes place during a dream, the same as what has been inspire to some of the Holy prophets in their dream. Objectives: Although one third of human life is spent in sleep, mysteries of sleeping are not completely cleared yet. People, who did not naturally sleep, are faded and angry persons. On the contrary, those people who enjoy a reasonable amount of sleep are joyful persons and they feel vitality and excessive power within themselves when they are awake. Sleep is a sign of Gods’ power and it is related to the spirit of human, while the spirit is a world full of secrets itself. Islam expresses wonderful and fascinating notification and instructions about subject of sleeping and dreaming. Materials and Methods: This study will examine the sleeping issue based on existing books and documentation by pedagogic study method and specially concentrates on review of Quran verses and their comparison upon the above mentioned subject. Results: sleeping and dreaming in humans are instinctive. For explaining the importance of sleeping, it would be satisfactory to say “if the sleeping can be prevented in a person, it will cause death”. Sleeping has an important role in human health. Regulation of sleep or its disorders, will directly affects health or disease of people. During sleeping, the lost body forces are recovered. The remained Toxic and waste substances that are produced during the metabolism, i.e. cellular feed system, are worn out from the body’s cells. Then the body cells save recovered energy and ability for our waking time. Conclusions: time of sleeping and resting, amount of sleeping, states of before sleeping, quality of sleeping and states after sleeping have important role in human health. Sleeping issue is a subject that draws special attention in Islamic medicine and traditional medicine under title “Setta Zarouriah”. Here in this study some portion of complex aspect of sleeping is examined.