The purpose of this study was to understand different attachment styles and sexual jealousy and their relevancy on different circumstances in the intimacy relationship of university students. The questionnaire survey was used in this study. University of Kaohsiung public and private university students and large Kaohsiung area network used of the students, a total of 870 effective sample survey and the following conclusions: First, for "gender," "past relationship experienced" there was a significant difference in the secure preoccupied and fearful attachment style for university students. "Love experienced" brought significant difference on the secure, fearful and dismissing attachment style. Then, there was also a significant difference in "fearful attachment style" for those who were involved in a love triangle. If someone had taken sexuality education related classes before, there was a significant difference in secure and fearful attachment style. Second, for "gender," "relationship status," "love experiences" there was a significant difference on the "sexual jealousy" for university students. Third, university students were associated with "secure attachment style," "preoccupied attachment style" and "dismissing attachment style" and "sexual jealousy." There was a high positive correlation between secure attachment style and sexual relationship.