Abstract: A liquid composite high-intensity sweetener, comprises a sweet substance and a solvent, wherein the sweet substance is one or combination of a plurality of the following components: aspartame, sucralose, acesulfame and neotame; and the solvent comprises water and one or combination of a plurality of the following components: ethanol, propylene glycol, phosphoric acid, citric acid, lactic acid, acetic acid, malic acid, ascorbic acid, glucose acid, tartaric acid, acetate, lactate, citrate, phosphate, sorbic acid, sorbate, benzoic acid and benzoate. In addition, the present invention further claims a method for preparing the liquid composite high-intensity sweetener. The liquid composite high-intensity sweetener not only has sweet taste similar to sucrose and good quality, but also is mixed uniformly without particles remained; the actual requirements of production and consumption are well met.