The purpose of this study was to estimate compensatory movement of the posterior oropharyngeal wall after tongue reconstruction.This study involved 13 patients who underwent tongue resection and reconstruction for tongue cancer between November 2011 and February 2015.We measured the distance between the anterosuperior point of the second cervical vertebrae and the posterior oropharyngeal wall in the resting position and during the swallowing phase using videofluorography.The ratio of these numbers （motor ratio） was calculated in the early postoperative period （within 6 months after surgery） and middle period （more than 6 months）.Thirteen patients （7 males and 6 females） with an average age of 62.7 years consisted of 6 half resections, 6 subtotal resections and 1 total resection and they were reconstructed with 9 abdominal flaps, 1 anterolateral thigh flaps and 3 forearm flaps.The average motor ratio was 2.53 within 6 months post-surgery and 3.03 over 6 months post-surgery.Compensatory function was not needed when the residual tongue worked well and had enough volume.On the contrary, compensatory function increased when the residual tongue function and volume were not enough.In the cases of tongue resection with lateral oropharyngeal wall, there were cases that compensatory function did not work.The residual tongue function and compensatory function should be considered when planning reconstructive surgery as it will likely contribute to improvement of the swallowing function after surgery.