The invention belongs to the technical field of medical medicines, and particularly relates to 5 percent glucose substitution liquid and a preparation method thereof. By the substitution liquid, the problem that medicines are needed to be prepared specially due to reduction of a medicinal effect or discomfort in patients caused by some medicines and the conventional glucose injection compounding agent is solved. The preparation method for the 5 percent glucose substitution liquid comprises the following steps of: adding the following components: 5,000 milligrams of glucose, 573 milligrams of sodium chloride, 346 milligrams of anhydrous sodium acetate, 49 milligrams of potassium acetate, 32.2 milligrams of magnesium acetate tetrahydrate and 30 milligrams of sodium metabisulfite into 100 milliliters of water for injection, concentrating, diluting, filling and sterilizing. The 5 percent glucose substitution liquid can regulate the physiological functions of human bodies and change the fussy process of preparing reagents by nurses, and is convenient to use, high in safety and stable in curative effect.