Background: Obstructive sleep apnea (OSA) is a prevalent sleep disease that, if left untreated, can result in considerable morbidity and mortality. Residents in family medicine play a significant role in the diagnosis and treatment of OSA. However, few studies have been undertaken to evaluate their OSA knowledge, attitudes, and confidence. Consequently, the purpose of this study was to evaluate the knowledge, attitudes, and confidence of family medicine residents regarding OSA, as well as to investigate the association between these variables and demographic parameters. Methodology: This cross-sectional study was conducted among Saudi Arabian family medicine residents in cluster 2 of the Ministry of Health. A self-administered survey was utilised to collect data on OSA-related knowledge, attitudes, and confidence. The questionnaire comprised of 18 knowledge questions, five attitude questions, and five confidence questions. The information was examined using descriptive and inferential statistics. Results: 110 residents in family medicine participated in the study. Results indicated that family medicine residents have modest OSA knowledge. The average knowledge question score was 7.77 out of 18. (43.2 percent). The study also revealed that family medicine residents are aware of the significance of OSA as a clinical disease but lack confidence in diagnosing and treating patients with OSA. The training level was the most influential demographic component in predicting OSA knowledge scores, attitudes, and confidence. R3 level inhabitants had the greatest mean knowledge and attitude scores about the significance of OSA. Conclusion: The study reveals the knowledge gaps and lack of confidence among family medicine residents about the management of OSA patients. The findings imply that educational programmes focused at enhancing the knowledge of family medicine residents about obstructive sleep apnea may improve the quality of treatment offered to patients with obstructive sleep apnea. In addition, demographic characteristics such as training level and expertise have a crucial impact in affecting the confidence and attitude of family medicine residents toward OSA. To ensure that family medicine residents have a solid foundation in OSA management, educational interventions should be targeted at earlier levels of training.