Objective:To study the application of forward optimization technique in the intensity-modulated radiation therapy for nasopharyngeal carcinoma. Methods:From March 2003 to August 2010, 92 patients with nasopharyngeal carcinoma underwent intensity-modulated radiation therapy and were considered in this retrospective study. All treatment plans were designed according to contour-based optimization technique based on the patient’s anatomy, i.e., on the outlined structures like planning target volume and organs at risk, or the apertures can be defined according to certain isodose-lines achieved with an open field. Results:The dose distributions and dose-volume histograms met the demand of treatment in all patients. The doses of 95 percent(D95)of planning gross tumor volume of nasopharyn (PGTVnx) were greater than or equal to 70 Gy for all patients(92/92). The D95s of planning target volume of high risk region (PTV1) were greater than or equal to 60 Gy for 85 patients(85/92), and the D95s of planning target volume of low risk region (PTV2) were greater than or equal to 54 Gy for 82 patients(82/92). The maximum doses of cord were 45 Gy for all patients(92/92). The mean number of segments was 39(range,29~65) and the median was 41. The mean total monitor units (MU) were 720.5(range, 586.9~1 050.7) and the median was 758.6. The mean treatment time was 15.7 min (range, 11.6~23.5 min) and the median was 16.5 min for 65 patients underwent after October 2006. Conclusion:This study suggests that intensity-modulated radiation therapy appears to be a new effective option for nasopharyngeal carcinoma. The satisfactory dose distributions can be obtained using reasonable contour-based optimization technique. The superiorities of contour-based optimization such as deep decreased segments can reduce total MU and shorten treatment, get more efficient treatment outcomes.