Pulmonary endometriosis (PEM) is a rare disease with diverse clinical manifestations, most commonly presenting as hemoptysis, while patients presenting solely with pulmonary nodules are less common. Here, we report three female patients (aged 32, 19, and 46 years, respectively). One patient sought medical attention due to hemoptysis during menstruation, while the other two had no obvious symptoms and were found to have pulmonary nodules during routine physical examinations. Two patients had a history of cesarean section, and one had a history of miscarriage. Pathologically, one patient of PEM showed extensive hemorrhage in the alveolar spaces, with fragmented endometrial glandular epithelium observed within the hemorrhagic foci. The other two patients exhibited proliferative endometrial glands and stroma, surrounded by old hemorrhage. Immunohistochemistry revealed that the endometrial glands and stroma in all three patients were positive for estrogen receptor, progesterone receptor, and vimentin, with CD10 positivity in the endometrial stroma. All three patients were definitively diagnosed as PEM by pathology and underwent thoracoscopic pulmonary wedge resection. Follow-up periods were 18, 31, and 49 months, respectively, with no recurrence observed in any of the patients.