Aim To investigate missed opportunities to reveal existing but not formerly diagnosed coronary heart disease cases and related risk factors in primary health care. Methods The study comprised 850 people aged over 30 years with no known history of coronary heart disease, receiving health services from a primary care center located in a suburban area of Antalya, Turkey. Data on their age, gender, education level, health insurance status, income, smoking behavior, and physical activities were collected. Undiagnoscd coronary heart disease patients were determined by the Rose questionnaire, physical examination, and electrocardiogram. Height and weight, blood pressure, serum glucose and cholesterol levels were measured, and body-mass index and waist-hip ratio calculated. Each patient was given a risk score regarding age, smoking behavior, systolic blood pressure, and cholesterol levels. Estimated risk ratio of each person for developing coronary heart disease in the next decade was determined. Results The number of formerly undiagnosed coronary heart disease cases was 126 (14.8%). Overall mean (+/- standard deviation) risk score for developing coronary heart disease in the next decade in study group was 6.1 +/- 6.8. Diseases facilitating development of coronary heart disease: hypertension, diabetes, and hypercholesterolemia were present in 255 (30.4%), 70 (8.2%), and 364 (43.4%) participants, respectively. Obesity was detected in 315 (37.1%) subjects and there were 222 (26.1%) current smokers. For patients who attended primary health care, the estimated percentage risk for developing coronary heart disease in the next ten years was 7 to 45% in men and 2 to 45% in women. Conclusion Opportunities to reveal coronary heart disease and its risk factors are being missed in primary care. Measures should be taken to ensure timely diagnosis of coronary heart disease and related risk factors.