In fact, the difficulty of comparing each college entrance examination paper is of little significance. Because the college entrance examination, as a selective examination, is different from the accepted examination of the course, the most important thing is that the examination paper should have good discrimination (appropriate variance) and validity. Setting each question according to a certain difficulty coefficient should be subject to the discrimination setting of the whole test paper, which is conducive to the objective and fair selection of candidates. According to the data analysis of several years, it should be around 0.6.