Prostate cancer is predominantly a disease of older men. Patients generally present with urinary symptoms and rarely with metastatic disease. Prostate cancers most often have metastasis in regional lymph nodes, i.e the obturator and internal iliac nodes, by hematogenous or lymphatic spread, but metastasis to the supradiaphragmatic lymph nodes or generalized lymphadenopathy is rare. Generalized lymphadenopathy is seen in many metastatic neoplasms, especially in lymphoma and lung cancer. It is very rare in prostate cancer. We present an unusual case of a 67-year-old male with metastatic prostate cancer with generalized lymphadenopathy mimicking malignant lymphoma or lung cancer. The biopsy result indicated metastatic adenocarcinoma and prostate was found to be the origin. Diagnostic and therapeutic approach in this case is also discussed in the light of the literature.