Extramedullary plasmacytoma (EMP) is a rare disorder that typically occurs in the upper airway. Although the condition rarely arises in the lungs, a few cases have been reported. Here, we report a case of pulmonary plasmacytoma in 66-year-old man, who had been treated with VAD (vincrestine, adriamycin, dexamethasone) chemotherapy for multiple myeloma. The patient had been declared clear of multiple myeloma after 4 cycles of chemotherapy. Three months later, the patient had multiple masses visible on computed tomography (CT) and on positron emission tomography-computed tomography (PET-CT) with hot uptake. Subsequent studies using CT-guided needle biopsy and immunohistochemical stain showed pulmonary plasmacytoma. Bone marrow biopsy, serum, and urine M protein tests were repeated, showing no evidence of multiple myeloma. Pulmonary plasmacytomas, as extramedullary plasmacytomas, were considered an isolated manifestation of multiple myeloma recurrence. We treated the patient with concurrent chemoradiotherapy and the pulmonary plasmacytomas regressed dramatically.