Learn the point of view by sex to inquire into married men and women being in the difference on the cognition to the marriage and the affairs in this thesis. In this study, the participants are all live or work in Kaohsiung region. The researcher makes use of to choose a fill type questionnaire and arouses to fill to answer the interest, and finds out to fill personal opinion of answering from the questionnaire. The research is found as follows: 1. To the advantage and weakness of the marriage, male and female married have the same point of view. 2. The male and female married has part of cognition different view in the advantage and weakness of marriage. The affairs brings men and women all have "the feeling for loving", but the male values "sexual of new experience" more double vision, female get " quilt affirmation just toward the strength in the affairs". 3. The person who never have affairs thinks that the affairs will make marriage broken, but an extramarital affair mostly is not the sake of affairs and divorce.