Rationale and Background: : Over the past decade, dengue fever cases have increased, along with the expansion of mosquito populations. In Vientiane Capital, dengue fever remains a very serious public health concern, with fatal consequences if left untreated. Dengue fever impacts all populations, however, no study has specifically examined dengue fever prevention behaviours among secondary school students in Vientiane Capital. Objectives: : To assess preventative, and risk mitigating behaviors regarding dengue fever among secondary school students in Vientiane Capital. Methodology: : A cross-sectional descriptive study was conducted with 371 students between 10 and 15 years old currently attending secondary school in Vientiane Capital, Lao PDR. A self-administered questionnaire was completed. The data was subsequently summarized using descriptive statistics. Results: : The result showed that students had low level knowledge about dengue fever (2.5 ± 0.54). Overall knowledge of dengue fever and dengue fever prevention behaviors were similarly low (2.9±0.29). These results highlight the need for continued efforts to improve students’ knowledge of dengue fever prevention strategies and symptoms to reduce the risk of dengue transmission in schools. Conclusion: Students exhibited low levels of knowledge and poor prevention behaviours regarding dengue fever. Health education programs should be enhanced to improve students’ understanding of dengue prevention and control practices.