The invention relates to a preparation method and application of a high-activity tetranuclear polymer, and discloses a tetranuclear copper compound containing difluoro-oxamide ligands, and a preparation method and application thereof. The structural formula of the tetranuclear copper compound is shown as below. The preparation method includes the following steps: dissolving 2 mmol of oxamide mononuclear copper ligands in 10-20 ml of methanol, dissolving 2mmol of copper salts in 5-10 ml of methanol, adding the dissolved copper salts to the methanol solution of the mononuclear copper ligands tocarry out a reaction at 60 DEG C for 1 hour, adding a methanol solution, in which 2 mmol of 1,10-phenanthroline ligands are dissolved, to the mixed solution of the ligands, carrying out reflux at 60 DEG C for 5 hours before filtering, and slowly volatilizing filter liquor for 1 week to obtain a blue blocky crystal, namely the tetranuclear copper compound containing the difluoro-oxamide ligands. The copper salts include copper perchlorate, copper chloride, copper bromide and the like. Compared with currently used platinum-based anticancer compounds, the tetranuclear copper compound has the advantages of high anticancer activity, low cost, simplicity in preparation, and the like. It is found for the first time that the synthesized compound has high activity in sugar reduction, providing a new way for developing related drugs.