Background: Sexually transmitted diseases (STDs) have been a increasing problem worldwide with an estimation of 340 million new cases each year. STDs are one of the top five reasons of seeking health care in the developing countries. Aim: The aim was to investigate the knowledge, attitudes and beliefs regarding STDs among young adults in two vocational schools in Ho Chi Minh City, Vietnam and also compare the genders regarding the issues. Method: A descriptive and comparative study was used. The 455 students between the age of 15 and 24, both male and female, participated voluntarily to answer a questionnaire. Dorothea Orem’s self-caring theory was provided as theoretical framework. Results: The students showed a low knowledge regarding STDs. Small differences between the genders could be seen regarding knowledge where the males had a higher knowledge regarding symptoms of STDs. Conclusions: The adolescents had lack of knowledge about STDs and no greater difference between genders have been shown. The traditional attitudes must change and follow the development of Vietnam. Further research should be performed to find out if there is any difference between students in rural and central areas of Vietnam.