Objective To investigate the clinical outcome of free thoracoacromial artery perforator (TAAP) flap in the reconstruction of tongue and mouth floor defects after radical resection of tongue carcinoma. Methods Between May 2010 and February 2015, 11 cases of tongue carcinoma underwent radical resection and reconstruction of tongue and mouth floor defects with free TAAP flaps. The locations of tongue carcinoma were the lingual margin in 7 cases, the ventral tongue in 2 cases, and the mouth floor in 2 cases. According to Union for International Cancer Control (UICC) TNM stage, 3 cases were classified as T4N0M0, 3 cases as T4NlM0, 2 cases as T3N1M0, 2 cases as T3N2M0, and 1 case as T3N0M0. The disease duration ranged from 3 to 28 months, 10.6 months on average. The tumor size ranged from 6.0 cm×3 cm to 10 cm×5 cm. The TAAP flap ranged from 7.0 cm×4.0 cm to 11.0 cm×5.5 cm in size, and 0.6-1.2 cm (0.8 cm on average) in thickness, with a pedicle length of 6.8-9.9 cm (7.2 cm on average). Results All 11 flaps survived, the donor site was closed directly and healed primarily in all cases. The patients were followed up 12-24 months (17.2 months on average). The reconstructed tongue had satisfactory appearance and good functions of swallowing and language. No local recurrence was observed during follow-up. Only linear scar was left at the donor site, and the function of pectoralis major muscle was normal. Conclusion The TAAP flap is an ideal choice in the reconstruction of tongue defect after resection of tongue carcinoma, which has good texture, appearance, and function results.