Conclusion. IMRT provided better conformity, less toxicity and better function restoration for advanced hypopharyngeal carcinoma after major surgery with ileocolic flap reconstruction. Objectives. To compare the results of adjuvant conventional radiotherapy (2DRT) with intensity modulated radiation therapy (IMRT) for locally advanced hypopharyngeal cancer after resection and ileocolic free flap reconstruction and to design treatment plans for those two modalities plus 3D conformal radiotherapy (3DCRT) for dose distribution comparison. Methods. 13 locally advanced hypopharyngeal cancer patients were enrolled, 8 treated with 2DRT and 5 with IMRT. Different plans were planned for 3 IMRT-treated patients for comparing dose distribution. Results. After major surgery, patients treated with IMRT had less toxicity and better functional restoration than those with 2DRT. IMRT and 3DCRT both showed lower dose to the spinal cord than did 2DRT. Only IMRT showed reduced dose to ileocolic flap.