In previous studies, there was an apparent lack of health education about dengue fever (DF) among the Saudi population. Therefore, we conducted this study to assess the knowledge, attitude, and practices (KAP) about dengue fever among the Jazan region population, which is one of the most prevalent diseases in the region in Saudi Arabia (KSA). This was a cross-sectional and community-based study. The adult population was divided into governorates according to the regions that were close to each other, and then a convenient stratum was selected from each region. Next, random sampling was applied. Data were collected using a self-administered questionnaire. Exclusion criteria were young people (<18 years old) and health workers. Data analysis was performed using descriptive statistics, the Pearson’s correlation coefficient, and multiple linear regression. Of the 392 participants in this cross-sectional study, 59.18% were male, 76.28% were aged 18–35 years, 72.96% had a university degree, and 63% had a monthly income of less than SAR 5000 (USD1 = 3.76). The scores (mean ± SD) for KAP regarding DF among the responders were 22.77 ± 7.9, 22.68 ± 7.24, and 25.62 ± 9.4, respectively. KAP constructs were positively correlated according to the Pearson’s coefficient. In multiple linear regression analysis, males were favorably and substantially linked with attitude score (β = 2.76, p = 0.001) and negatively associated with practice score (β = −2.45, p = 0.023). No-degree participants scored lower on knowledge (β = −2.78, p = 0.003). There is potential for more research in Saudi Arabia to increase the generalizability to reduce the impact of dengue epidemics.