Arterial hypertension has the largest prevalence (37.50%) in Croatia among all cardiovascular disease risk factors. The specific mortality from complications of cardiovascular diseases amounts 39.94% of the general mortality, therefore we aim at blood pressure values below 140/90 mmHg. Nevertheless, 42.18% of cardiac patients with arterial hypertension do not achieve target blood pressure values in spite of taking at least three antihypertensive medications at an adequate dosage, of which one is a diuretic. Among the most common causes of therapeutic failure is lack of patient compliance. Consequently 13.61% of cardiac patients with arterial hypertension do not achieve the target blood pressure values. This cross-sectional study was conducted in the Clinic for Cardiovascular Diseases, University Hospital Centre Sisters of Charity, from December 2016 to April 2017, and included 154 cardiac patients; 147 with arterial hypertension and 120 with dyslipidemia. To evaluate patient compliance the 8-item Morisky Medication Adherence Scale (MMAS-8), a structured self-report measure of medication-taking behavior, was administered. Regarding cardiac patients with arterial hypertension, 22.45% were poorly adherent and that percentage was approximately the same (22.50%) in cardiac patients with dyslipidemia. With a statistical significance lower than 5%, we can deduct that the ones poorly adherent are cardiac patients with arterial hypertension and systolic blood pressure values greater than 140 mmHg, cardiac patients with arterial hypertension and dyslipidemia and systolic blood pressure values greater than 140 mmHg, as well as cardiac patients with resistant hypertension. When we talk about cardiac patients with dyslipidemia, female patients are more poorly adherent than male, and so are patients with plasma cholesterol levels greater than 4.5 mmol/L. Cardiac patients with arterial hypertension who may not be aware of the longterm benefits of antihypertensive therapy are poorly adherent. Therefore, lifelong learninig and partnership in making decisions contributes to good patient compliance.