The invention belongs to the technical field of herbicide, and provides a thickening diquat aqueous solution formula, a preparing method and a using method. The thickening diquat aqueous solution is prepared from 50 parts of diquat mother liquor, 20 parts of thickening surface active agent, 10 parts of organic silicone emulsion, 8 parts of propylene glycol methyl ether acetate and 12 parts of water. The thickening surface active agent is prepared from, by weight, 5 parts of ammonium chloride, 25 parts of coconut oil monoethanolamide, 30 parts of lauric acid amido propyl glycine betaine, 10 parts of polyvinylpyrrolidone and 30 parts of water, the organic silicone emulsion is prepared from, by weight, 22 parts of hydroxyl silicone oil, 18 parts of polyether polyamine block silicone oil, 4 parts of XL-40-, 3 parts of XL-70-, 1 part of defoamer, 2 parts of acetic acid and 50 parts of water. According to the thickening diquat aqueous solution formula replaces original paraquat, the compounded formula can strengthen dwell time of agent liquor in the surface of plants, effective component loss is reduced, and the agent effect is improved.