The author described an adenoleiomyomatous hamartoma of the lung. The hamartoma was well circumscribed and measured 2.5x3.0x3.0 cm. This type of hamartoma is a rare lesion in literature described only in single cases, and without performed immunohistochemistry. In our case, the hamartoma was formed by slit or irregular glandular-like spaces lined by cuboid or columnar epithelial cells. Located around these spaces, fascicles and bundles of smooth muscle tissue with a positive antibody reaction to desmin, smooth muscle actin, and calponin, were found. Reaction with CD34 and S100 protein antibodies was negative. In the discussion, the author draws attention to disunity of terms and nomenclature of similar lesions. After three years of post-operative clinical follow-up, the patient is asymptomatic and without any signs of lung disoder.

        Key words: adenoleiomyomatous hamartoma – lung – morphology – immunohistochemistry