WDLPS are very rare retroperioneal tumors that can reach huge size before becoming symptomatic. The aim of this article is show the diagnostic management and the surgical approach to giant WDLPS. A standard treatment has yet to be established because the pre-operative diagnosis is very difficult. We present a case of a 69-year-old male patient with progressive increase of abdominal girth, weight loss and light abdominal pain and with an abdominal mass of over 15 kg that displaced the right kidney. A complete tumor resection and right nephrectomy were performed. Histology revealed a well-differentieated liposarcoma. CT scan is the most common imaging technique and laparotomic open radical resection represent the most common surgical approach.