Abstract: Objective To understand the knowLedge,attitude,and practice(KAP)of sex in college students and to discuss the policies for sexeducation and reproduction health.Methods Orevall 1232 students in Shanghai Custom College and Shanghai Second Poly technic University were randomly selected and surveyed.Results Among the students surveyed,22.56% knew a lot about reproduction health;46.92% had some knowledge,and 30.52% had a little.As for sex behavior before marriage,36.77% of the students approved of it;11.61% of them had sexual experience and 60.8% thought people should be responsible for the sexactivity.76.92% of students with sex bahaviors adop ted contraception measures and 19.58% of them used condoms.52.75% of the students believed that hom osexuality was different sexual orientation.2.92% of them had hom osexual behavior.26.95% of the male students approved of cohabitation before marriage.For female students,24.55% approved of it.However,a clear distinction existed between freshmen and sophomores when talking about the issue.17.71% of the freshmen approved of cohabitation before marriage while 24.91% of the sophomores approved of it.Conclusion The college students lack reprodution health knowlegde.There are differences in sexattitude and behavior between college students of different grade and gender.