Primary sarcomas of the mediastinum are relatively rare. This article reviews the surgical outcomes of 21 cases diagnosed with localized mediastinal sarcomas receiving multidisciplinary treatment modalities in Sichuan province, China, from January 1996 to January 2011. Twenty-one cases of histologically diagnosed primary mediastinal sarcoma undergoing surgical treatment were reviewed retrospectively. Disease-free survival (DFS) and overall survival (OS) were statistically analysed. All the patients presented with localized tumours consisting of 5 females and 16 males with a median age of 41.0 years (range: 9.0-68.0 years). Among all cases, 17 (81.0%) had an Eastern Cooperative Oncology Group performance status score of < 1 at diagnosis. Eight (38.1%) underwent macroscopically complete resection (R0-R1) and 13 (61.9%) had incomplete resection (R2). Ten (47.6%) received postoperative radiotherapy and 7 (33.3%) postoperative chemotherapy. The median DFS was 17 months (range: 0.4-79.8 months) and the median OS was 27.2 months (range: 0.4-79.8 months). Patients receiving complete resection showed significantly improved DFS (P = 0.031) and OS (P = 0.035) compared with those with incomplete resection. Neither postoperative radiotherapy nor chemotherapy significantly improved DFS (P = 0.770, P = 0.756) or OS (P = 0.905, P = 0.738). However, 7 patients (R2) and 2 (R0-R1 and grade 3) had improved local control with a local recurrence-free survival of 28.9 months (range: 7.6-73.2 months). Complete resection should be preferentially attempted compared with incomplete resection and postoperative radiotherapy might yield good local control.