Objective To investigate cl inical effect and prognosis of the modified sternocleidomastoid (MSCM) myocutaneous flap for reconstruction of tissue defects in patients with oral carcinomas undergoing tumorectomy. Methods From April 2001 to January 2007, 43 patients with large or medium-sized tissue defects because of oral carcinomas radical operation were treated with MSCM myocutaneous flap. There were 31 males and 12 females with an average age of 58.5 years(25-76 years). The disease course was 25 days to 14 months (4.5 months on average). There were 27 cases of well-differentiated squamous cell carcinoma (SC), 14 cases of poorly-differentiated SC, 1 case of rhabdomyosarcoma, and 1 case of adenoid cystic carcinoma. Affected locations were tongue in 25 cases, mouth floor in 11 cases, lower gingiva in 4 cases, and buccal mucous membranes in 3 cases. According to 2002 International Union Control Cancer criterion for cl inical stage, there were 3 cases of stage I, 13 cases of stage II, 7 cases of stage III, and 20 cases of stage IV. Both the ranges of soft tissue defects and the flap were from 4 cm × 3 cm to 8 cm × 6 cm. The vital ity of the flaps and the heal ing of wounds were observed postoperatively. The function restoration of deglutition and dehisce were observed during the follow-up period. Results Necrosis of quarter MSCM myocutaneous flap occurred in 3 cases 1 week after operation, wounds healed by secondary intention after dressing; other flaps were survival. Infection with fluidify occurred at the donor site of 2 cases, wounds healed by incision and drainage; other incision at the donor sites healed primarily. No arterial or venous crisis occurred in all 43 flaps after 48 hours of operation. Thirty-nine patients were followed up for 6 months to 6 years. The 3 patients with buccal carcinoma could open their mouths normally. The function of deglutition and pronunciation were recovered in 24 patients with tongue carcinoma. Only 3 patients needed to have soft diet after operation. In 26 patients who were followed up above 2 years, oral metaplasia of the the skin flaps epithel ium was observed. Four patients and 2 patients recurred and died after 6 months and 1 year of operation, respectively.Two patients received the second operation after 6 months because of the metastatic lymph node, and survived up to now. The 2-year survival rate was 85%. Conclusion MSCM myocutaneous flap is simple to perform and effective in reconstruction of tissue defects for patients with oral carcinomas. It has active effect to recover the function of oral and axillofacial region and elevate l iving qual ity of patients.