The purposes of this study were to examine the current situation pertaining to the teaching of sex education and identify barriers to teaching sex education among Thai health education teachers. A survey questionnaire was administered to 193 health education teachers who participated in this study. The questionnaire was comprised of three parts: (1) demographic questions, (2) the current status of sex education in Thailand, and (3) the barriers to teaching sex education. The third part was comprised of teacher characteristics, curriculum and multimedia, and environmental factors. The findings focused on the main effect interaction analysis between a dependent variable (gender, age, level of education, etc.) and the three factorial scales generated by using the Factor Analysis Procedure from the questionnaire. There were no significant differences found between the dependent variables and the three factors associated with teaching based on Analysis of Variance (ANOVA) at p=0.05. Using descriptive statistics, we found teachers held interesting perspectives on factors surrounding sex education. So, although there were no significant differences in the findings, the study indicates that health education teachers contribute to the quality of teaching and the learning process of sex education. They play a critical role in designing and implementing sex education courses. (Contains 24 figures and 3 tables.)