━━ Background. Ectopic ACTH-producing tumors are common in patients with malignant lung tumors, especially those with neuroendocrine tumors, and are prone to cause Cushingʼs syndrome. Case. We report an 82-year-old woman with a 1 month history of general malaise, low-grade fever, and bilateral lower-extremity edema who was suspected of having ACTH-dependent Cushingʼs syndrome. Computed tomography revealed a nodule in the left lower lobe. Left lower lobectomy and lymph node dissection were performed. The pathological diagnosis was typical carcinoid, with positive immunohistochemical staining of ACTH. She was diagnosed with an ACTH-producing pulmonary typical carcinoid (pT1bN0M0, stage IA2). Postoperatively, while steroid therapy was being tapered, she developed Pneumocystis pneumonia and required ventilator management. Her oxygenation improved with the administration of trimethoprim-sulfamethoxazole and a steroid, and she remains alive without recurrence at or 7 years and 4 months after surgery. Conclusion. We reported the case of a patient with ectopic ACTH-producing pulmonary typical carcinoid with preoperative Cushingʼs syndrome, who was successfully treated with lobectomy and who survived but developed Pneumocystis pneumonia after surgery. We suggest that prophylaxis against PCP should be considered before starting therapy.