Pulmonary hemorrhage can occur due to various causes that can damage lung tissue. Primary causes include tumors (especially lung cancer), infections (such as pneumonia, tuberculosis, bronchitis), bronchiectasis, systemic diseases, and congenital anomalies. The main source of severe pulmonary hemorrhage is typically the bronchial arteries. These high-pressure vessels are responsible for approximately 80% of serious bleeding. Other potential sources of bleeding include aortobronchial fistulas, ruptured aneurysms, and non-bronchial structures like pulmonary vessels. One of the most common causes is tumors. As most lung cancers originate from the bronchial epithelium, the bronchial arteries are often found within the tumor tissue. Bleeding can occur from these vessels when the tumor erodes the bronchial tissue. Similarly, some infections can also lead to bleeding. For instance, fungal infections in the lungs can form cavitations; these cavities create an environment prone to bleeding, thus causing pulmonary hemorrhage. Systemic diseases can also lead to bleeding by affecting the lung parenchyma, although their incidence is lower compared to other causes. Among congenital causes, vascular anomalies are the most frequently observed. However, congenital causes as a whole are rare contributors to pulmonary hemorrhage.