Introduction: Complementary and Alternative Medicineisbeing used along with evidence-based medicine among diabetic patients. In Saudi Arabia, itwas widely utilized among diabetic patients, and this was coupled with the high prevalence of diabetes.This study aimed to assess the knowledge, attitude, and practice of complementary and alternative medicine among diabetic patients in Eastern Province of Saudi Arabia. Methods: This is a cross-sectional study conducted among patients with type 2 diabetes attending primary healthcare centers in Eastern Province between the years 2022 to 2023. A self-administered questionnaire translated from English into Arabic was distributed. Results: Total of 381 diabetic patients, 54.1% were females and 46.2% were aged between 41 to 60 year-old. Poor knowledge of the basic facts of complementary and alternative medicine was found in 50.1% of the patients while 17.3% had moderate knowledge and the remaining 32.5% hada good knowledge level. Regarding the attitude, 40.7% showed positive attitudes, 48.6% neutral, and only 10.8% considered having negative attitudes. The prevalence of patients who were using complementary and alternative medicine products for the treatment of diabetes was 40.9%. Conclusion: Despite the lack of knowledge among diabetic patients regarding the basic facts of complementary and alternative medicine, a considerable proportion of them were using it and were seen to have an optimistic attitude regarding its beneficial effects. Identifying opportunities to foster the balanced use of complementary and alternative medicinethrough evidence-based guidelines and patient-centered approaches is warranted.