Every eighth woman in the world will be diagnosed with breast cancer. Available oral antitumor drugs are becoming more common and can improve quality of life in patients that are receiving adjuvant therapy. Previously mentioned therapy requires patients to take responsibility for taking the medication and to actively participate in the treatment process. That is why term adherence has become important in this context. Body of literature shows that adherence to oral antitumor drugs is often suboptimal. The purpose of this research was to determine the rate of adherence in patients with advanced breast cancer. The prevalence of depressive symptoms and influence of depressive symptoms on adherence was also questioned. Because lower adherence can lead to disease recurrence and higher mortality rates, it was important to determine the factors that can influence adherence and how to prevent them. Conducted research was observational and cross-sectional. Women over 18 years with advanced breast cancer (stage IV) that are on oral therapy were included in the study. Adherence was measured with validated MARS-5 questioner and the presence of depressive symptoms was measured with Beck’s depression inventory – second edition. Patients with advanced breast cancer included in the research had a high adherence rate, specifically their score was 24,04 (±1,653) out of maximal possible 25. The prevalence of depressive symptoms in patients with breast cancer, especially those with metastatic breast cancer is higher than in the general population. It is considered that depressive symptoms can lead to lower adherence and therefore cause worse therapeutic outcomes. Although almost 45% of patients had some form of depressive symptoms, the statistically important relationship between depressive symptoms and lower adherence was not found (p=0,455). Still, it is important to pay attention to patients with depressive symptoms because the chronic stress response which can contribute to depression in patients with cancer, can also lead to increased cancer invasiveness.