We report a case of hemorrhagic pulmonary oxalosis secondary to a noninvasive Aspergillus niger fungus ball. A patient with cavitary lung disease and hemoptysis developed progressive lung infiltrates and intractable metabolic acidosis leading to death. At autopsy, aspergillomas were identified in both the right upper and middle lobes surrounded by a large rim of necrotic and hemorrhagic parenchyma. Microscopic examination showed extensive crystal deposition and vascular thrombosis. Fungal growth was limited to the intraluminal mycelia, and no tissue or blood vessel invasion was present. Remote crystal deposits were also localized in the absence of fungal organisms to the contralateral lung and to the tubules of both kidneys. The crystals were birefringent in polarized light and stained with colloidal iron. X-ray powder diffractometry and electron impact ionization mass spectrometry identified the crystals as calcium oxalate monohydrate. Furthermore, non-necrotizing granulomatous lesions were identified in the lungs, liver, and spleen, consistent with sarcoidosis, and may have predisposed this patient to developing pulmonary aspergillomas.