[Object] In recent years, life style-related diseases, particularly circulatory system diseases caused by the tendency toward high caloric diet, the change in life style, lack of exercise, stress and so on increased and have became a serious social problem. These diseases are caused mainly by injures in blood vessels. To prevent injures in blood vessels, there has been required a vascular endothelial cell-protecting agent and a food having an effect of protecting vascular endothelial cells.[Means to solve] It is possible to provide an agent for alleviating, treating and preventing vascular failure and a vascular endothelial cell-protecting agent characterized by containing, as an effective ingredient, at least one active oxygen scavenger such as astaxanthin and tocotrienols; and a food, a drink and an animal feed each having an effect of alleviating, treating and preventing vascular failure and an effect of protecting vascular endothelial cells characterized by containing, as the effective ingredient, at least one active oxygen scavenger such as astaxanthin and tocotrienols.