We present here a 32-year-old male with advanced lately diagnosed, right sided retroperitoneal mass, which had been already treated due to progressive muco-cutaneous lesions clinically consistent with psoriasis, during recent four years. The advanced retroperitoneal mass resected surgically and reported as hyaline-vascular castleman disease with a dense focus of coarse calcification, on histopathology. Association of psoriasis and castlman disease is discussed in this case report. ####