The invention discloses a high-efficiency composite clarifying agent used for clarification and decolorization of a sugar liquid. The high-efficiency composite clarifying agent is composed of the following components in parts by weight: 100 to 200 parts of modified calcium phosphate, 2 to 5 parts of polyphenol oxidase and 2 to 5 parts of pectinase. The preparation method for the composite clarifying agent comprises the following steps: weighing the polyphenol oxidase and the pectinase according to the amounts described in the formula, dissolving the weighed polyphenol oxidase and pectinase into a phosphate buffer solution so as to obtain an enzyme mixed solution, then weighing the modified calcium phosphate according to the amount described in the formula, adding the modified calcium phosphate into the enzyme mixed solution under the condition of stirring, carrying out oscillating adsorption at 10 to 20 DEG C for 2 to 6 hours, and carrying out drying under a vacuum condition so as to obtain the high-efficiency composite clarifying agent used for clarification and decolorization of the sugar liquid. The high-efficiency composite clarifying agent provided by the invention is used forclarification and decolorization of the sugar liquid, can improve the efficiency of a decolorization procedure in sugar preparation, and reduces the production cost of sugar preparation.