Liposarcoma is a malignant tumor originated from adipose tissue, accounting for 20% of all soft tissue sarcomas. A 69-year-old man with anterior and posterior neck mass visited to our department and we performed an excisional biopsy in level I. Histopathological examination revealed liposarcoma, so we performed wide excision in anterior and posterior neck, and adjuvant radiotherapy. We report a unique case of well-differentiated liposarcoma on anterior and posterior neck with literature review. To our best knowledge, such case has not been reported earlier in Korea previously.