Barley， as the world′s fourth major cereals， is mainly used for animal feed and beer brewing. But its nutrition， functional component and healthy effects do not be regarded enough. In the last 10 years， barley production and deep-processing was faced with severe situation. The variety and composition of nutritional and functional substances in barley were described in detail. The characteristics of its effects to the human health were summarized. The review would provide references for the deep-processing and scientific consumption of barley.