Background and aims: Since cardiovascular diseases (CVDs) are the most common cause of morbidity and mortality in the world, this systematic review aimed to investigate the effectiveness and mechanism of aromatherapy on hemodynamic parameters in patients with CVDs. Methods: This review was performed in accordance with PRISMA guidelines. Using relevant keywords, an extensive search was done in 1.30.2022 in most important databases including Scopus, PubMed, Web of Science, and Google Scholar. A form was designed for recording data related to randomized clinical trials (RCTs), hemodynamic changes (e.g., heart rate, respiratory rate, systolic, and diastolic blood pressure), and information about possible mechanisms in non-RCT works was also extracted. Findings: In RCTs, aromatherapy with lavender (Lavandula angustifolia) oil, orange (Citrus sinensis) oil, lemon (Citrus limon), rose (Rosa damascena), and almond (Prunus dulcis) oil regulates pulse rate, respiratory rate, and blood pressure in patients with CVD. Aromatherapy can affect the sympathetic and parasympathetic systems through inducing local effects on veins, resulting in vasodilation, increased blood flow, and decreased peripheral resistance. Conclusion: Aromatherapy can be used as a complementary agent for regulating heart rate, blood pressure, and respiratory rate in patients with CVD. However, certain precautions such as allergic reactions in patients should be taken before administration.