Statins are hypolipemics commonly used in the treatment of hyperlipidemia or dyslipidemia and in the prevention of cardiovascular diseases. According to current literature data, attitudes and beliefs about statins are highly divided. The Beliefs about Medicines Questionnaire (BMQ) was developed for the purpose of assessing patient’s beliefs that affect the consumption of prescribed drugs and adherence to the given therapy. The aim of this diploma thesis was to investigate the attitudes and beliefs of patients on their medicines and specifically to statin in their therapy, to assess the knowledge and understanding of patients on their own statin therapy, to gain insight into their behavior and to evaluate their adherence. A cross-sectional observational study was conducted from June to August 2018 in collaboration with pharmacies from Zagreb and Poreč. The study involved adult patients who had been on statin therapy for more than three months. For each examinee demographic and relevant clinical data were gathered and patients fulfilled the BMQ questionnaire and 4-item Morisky Medication Adherence Scale (MMAS-4). The Ethics Committee from the Faculty of Pharmacy and Biochemistry from University of Zagreb has approved the implementation of this study. The study included 100 patients. The median age was 71 years (range 31-90) and patients had on average 4.78 ± 2.37 drugs (range 1-11) in their therapy. By counting the points of the statement for a particular group of BMQ questionnaire, the strength of the beliefs was measured in the concept representing the individual part of the questionnaire. The mean value of the group sum (General-Harm and Overuse, Specific-Necessity and Concerns) shows that patients do not have very strong beliefs in each of the concepts. The BMQ questionnaire groups were also analyzed in comparison with demographic and general data. The results have shown that if the education of the patient is lower, the beliefs on drug harm (p < 0,05) and necessity are more potent (p < 0,05). The BMQ questionnaire and adherence correlation analysis showed a statistically significant negative correlation between the beliefs of drug concerns and adherence (p = 0.015). In the qualitative part of the questionnaire, we found that most patients did not observe any problem with statin therapy (absence of indication, inefficiency of therapy, and problem of safety of statin therapy). For the first time, this study investigated statins and statin therapy attitudes and beliefs on a sample of the Croatian population using the Croatian version of the BMQ questionnaire and gave preliminary results for a better understanding of patients.