The invention relates to a preparation method and application of a novel high-efficient acidification corrosion inhibitor. The preparation method of the novel high-efficient acidification corrosion inhibitor is characterized by comprising the following steps: 1) synthesizing a benzyl brominated quinoline compound; and 2) diluting the benzyl brominated quinoline compound by using a solvent to the concentration of 8-15% by mass. The corrosion inhibition effect of the corrosion inhibitor disclosed by the invention is obviously better than that of a conventional acidification corrosion inhibitor at the same temperature and the same concentration of the corrosion inhibitor; the corrosion inhibitor is transparent and clear after mixing with an acid solution, has no phenomena of stratification, turbidity and the like after 48 hours and can achieve the first-level index requirements of a standard in the petroleum industry; the corrosion rate of a P110 steel test piece in 15% (by mass) of an acid solution is far lower than the requirements of first-level corrosion inhibitor product indexes at the temperature of 90 DEG C of the standard'SY/T5405-1996' in the petroleum industry.