This article summarizes selenium s nature of being and chemical cycle ,utilizable range of organism,toxicity and toxicosis,transfer process of food chain and so on.

• 从硒的自然存在与化学循环、硒的生物效应、硒的毒性与中毒、硒的食物链传递等几方面对硒加以综述性的介绍,以对硒进行较全面的认识。