BACKGROUND: Elevated resting heart rate (HR ≥ 70 bpm) is a strong prognostic factor in coronary artery disease (CAD). Although beta-blockers are guideline-recommended first-line therapy, their real-world effectiveness in controlling HR remains unclear, particularly in Middle Eastern populations. This study investigated HR distribution, its correlates, and the association between HR-lowering drugs and HR control in a large Iranian cohort. METHODS: We analyzed 10,138 adults aged 35–70 years from the Fasa PERSIAN Cohort with sinus rhythm ECGs. HR was obtained from resting 12-lead ECGs. Logistic regression examined associations between demographic, clinical, and pharmacological factors and HR < 70 bpm. Multivariable models were further stratified by CAD and hypertension (HTN) subgroups. RESULTS: A total of 7119 subjects (mean age 48.6 ± 9.3 years; 43.4% men) entered this study, of which 803 (11.3%) had CAD. Overall, 48.6% had HR ≥ 70 bpm. Beta-blockers were used by 9.4% of participants (40% of CAD patients). Despite therapy, 47.2% of beta-blocker users had HR ≥ 70 bpm. In univariable analysis, male sex (OR 4.07, 95% CI 3.68–4.50), current smoking (OR = 2.59,95%CI:2.28–2.93), and higher physical activity were strong predictors of HR < 70 bpm, while diabetes, hypertension, and higher BMI were inversely associated. In multivariable analysis, beta-blocker use was associated with HR < 70 bpm in the total population (OR 1.64, 95% CI 1.36–1.98) and in HTN patients (OR = 2.35,95%CI:1.72–3.22), but not in CAD or CAD + HTN subgroups. CONCLUSION: Nearly half of CAD patients failed to achieve HR < 70 bpm despite beta-blocker therapy, highlighting suboptimal control. Beta-blockers were effective only in patients with HTN but not in CAD or CAD + HTN groups. These findings emphasize the need for tailored therapeutic strategies and physician education to improve HR management in CAD.