与圆有关的证明题带有一定的综合性、灵活性,除了要考虑与直线型有关的性质与定理外,关键还要抓住与圆有关的性质和定理．垂径定理及逆定理是圆的一个重要定理, 很多与圆有关的证明题都要用到这个定理来解决．本文以近年全国各地竞赛试题中的与圆有关的证明题为例,说明这类问题的解题思路。 The propositions related to circles have a certain degree of comprehensiveness and flexibility. In addition to the properties and theorems related to the linear type, the key is to grasp the properties and theorems related to circles. The vertical theorem and the inverse theorem are an important theorem of the circle. Many circle-related proofs must be solved using this theorem. In this paper, the problem of solving problems of this kind of problem is illustrated by the example of the circle-related proof in the contest examination questions in various parts of the country in recent years.