Abstract: Objective To explore the related factors of the increasing nutritional risk in esophageal cancer patients receiving chemoradiotherapy by means of nutrition assessment, facilitating the timely nutrition monitoring and intervention, and providing scientific basis for individualized nutritional support. Methods Between July, 2014 and July, 2015, 97 patients with esophageal cancer who were screened for nutritional risk were selected as the subjects. We used the European nutritional risk screening tool (NRS-2002) to screen nutrition risk of patients at admission and during the first to sixth week of radiotherapy, and then analyzed their correlation, as well as evaluating the nutritional status of those patients. Results Twenty-seven percent of the subjects had nutritional risk before chemoradiotherapy. This risk was gradually increased during chemoradiotherapy, reaching 44. 8% at the sixth week. For patients whose NRS-2002 score was ≤ 3 point and ≥ 4point at admission, 1 year overall survival rate was 91. 1% and 61. 9% respectively (P=0. 010). For patients whose highest NRS-2002 score was ≤ 2 point and ≥ 3 point during treatment, 1 year overall survival rate was 94. 2% and77. 5% respectively (P=0. 012). For patients whose lowest NRS-2002 score was ≤ 3 point and ≥ 4 point during treatment, 1 year overall survival rate was 93% and 55% respectively (P=0. 009). The NRS-2002 score at admission and the first week of radiotherapy was associated with the pre-albumin level (P=0. 000, 0. 002). The NRS-2002 score was associated with albumin at the third week of radiotherapy (P=0. 036). Conclusion Esophageal cancer patients who receive chemoradiotherapy have higher nutritional risk, influencing the treatment process and effect. Therefore, timely and effective nutrition assessment and intervention is very important.