ABSTRACT: INTRODUCTION: Liposarcoma is the most commonly diagnosed soft tissue sarcoma in adults and occurs predominantly in the lower limbs and retroperitoneum. Primary mediastinal liposarcomas are rare.They are often asymptomatic and when growing to large size the presenting symptoms are related to direct invasion or compression of other thoracic organs such as the heart, great vessels and lung. CASE PRESENTATION: A case of a 68-year-old man with primary mediastinal liposarcoma involving the diaphragm and pericardium and successfully managed by complete surgical excision is presented. The patient's postoperative course was uneventful with no evidence of recurrence 9 months after the operation. CONCLUSION: Surgical removal is the optimal treatment for a mediastinal liposarcoma. If the entire tumor can not be resected, surgical debulking often results in symptomatic relief. International literature has demonstrated that recurrent disease occurs and therefore a long-term careful follow up is required.