Here, we report the case of cutaneous metastases from testicular diffuse large B-cell malignant lymphoma (DLBCL) concurrent with Bowen disease evaluated with 18F-fluorodeoxyglucose positron emission tomography-computed tomography (18F-FDG PET-CT). A 60-year-old male underwent orchiectomy to remove his left testicle because of DLBCL. Multiple skin lesions appeared 1 month postoperatively. Furthermore, an intractable erythematous plaque localized to the right lower leg was present from 2 years before the operation. 18F-FDG PET-CT images revealed multiple skin lesions with marked FDG uptakes in the face, neck, and thigh of this patient, as well as a lower leg lesion with minimal FDG uptake. Biopsy of both lesions revealed cutaneous metastases from DLBCL and Bowen disease (BD) of the lower leg lesion. 18F-FDG PET-CT images following chemotherapy and resection of BD demonstrated no FDG uptake.