The invention relates to a functional beverage for improving eyesight and reducing blood pressure, blood sugar and blood fat. The functional beverage is a beverage or healthcare beverage which is prepared according to the following processes: taking medlar, chrysanthemum, mulberry, semen cassiae, hawthorn and the like as raw materials; extracting; clarifying; preparing; sterilizing; and packaging. The functional beverage for improving eyesight and reducing blood pressure, blood sugar and blood fat has the functions of clearing liver, improving eyesight and reducing blood pressure, blood sugar and blood fat, and has an excellent therapeutic effect for eye disease patients who suffer from myopia, eyestrain, presbyopia, cataract, eye pain, vitreous opacity, and the like. The functional beverage provided by the invention tastes sweet. After the functional beverage is drunk for a long time, the functions of preventing and curing eye diseases, eliminating eyestrain, promoting eyesight, reducing blood pressure, blood sugar and blood fat and the like can be achieved. A preparation method of the functional beverage for improving eyesight and reducing blood pressure, blood sugar and blood fat is characterized in that more than two eyesight-improving intelligence-promoting beverages or other healthcare beverages can be prepared according to the formula and the beverage production technology. According to the formula of the functional beverage for improving eyesight and reducing blood pressure, blood sugar and blood fat, the functional beverage is composed of the following raw materials in proportion: 10-30% of medlar, 10-30% of chrysanthemum, 10-30% of mulberry, 10-30% of semen cassiae, 10-30% of hawthorn, and the like.