Background: Sexually transmitted infections (STIs) are a major health problem. Awareness about their transmission, prevention, testing, and treatment is important, especially among young adults. This study aimed to assess STI awareness among adults in selected coastal communities of Kanyakumari district, Tamil Nadu.

Methods: A cross-sectional study was conducted among 150 adults aged 18–30 years. Data were collected using a printed questionnaire administered in selected coastal communities. The questionnaire included questions about STI transmission, symptoms, prevention, testing, and treatment. The data were analysed using frequencies and percentages.

Results: The study included 62 (41.3%) males and 88 (58.7%) females. Among the participants, 60 (40%) were students, 40 (26.7%) were employed, and 50 (33.3%) belonged to other occupational groups. Of the recorded responses, 90 participants knew that condoms could help prevent STIs, and 75 knew that STI testing was available. However, some questionnaire responses were incomplete, so the overall level of STI awareness could not be clearly determined.

Conclusion: Awareness about STIs is important for preventing infections and encouraging early testing and treatment. Health education programmes may help improve STI awareness among young adults in coastal communities. Complete data are needed to draw clear conclusions.