The purpose of this study was to investigate the current situations of condom using behavior and its related factors among college students in Taiwan. There were two phases in the study. In phase I, 50 students from one college in the eastern, southern, middle and northern parts of Taiwan were selected to form a focus group, and were interviewed in order to further understand the reasons why they used and did not use condoms, so the information obtained became the basis of the questionnaire design. In phase II, by using stratified sampling (group sampling) method, a total of 1,200 freshmen from 12 colleges in Taiwan were selected. The results were as the followings after statistical analysis: Generally speaking, students continued to use condoms when they better understood the benefits of using condoms, such as preventing STDs, being a contraceptive, respecting the female partner and protecting oneself, decreasing the harm from rape, etc. The reasons for not using condoms are: afraid of ruining the atmosphere during the first sexual intercourse, worrying about losing sexual feelings, unexpected sexual act with impulse, embarrassing to request using the condom, and for women submitting to the male partner's sex act. (Contains 4 tables.)