Objective To evaluate the possible factors that may influence the resting energy expenditure (REE) in patients with newly diagnosed esophageal cancer. Methods Totally, 40 patients with newly diagnosed esophageal cancer were prospectively collected from November 2008 to June 2009 in Xinhua Hospital. Nutritional risk screening 2002 (NRS 2002) was performed. REE and body composition were measured using indirect calorimetry and bioeletrical impedence method, respectively. Results Twenty-seven (67.5%) patients were found with nutrition risk, and NRS score was negatively correlated with prealbumin ( r = - 0.444, P = 0.004) and albumin levels (r = - 0.386, P = 0.014). Measured REE and predicted REE values were ( 6770 ± 1360) and (6021 ± 841 ) kJ/d, respectively (P ＜ 0.001 ). Among all 40 patients, 57.5% of them were hypermetabolic,30.0% were normal, and 12.5% were hypometabolic. Stepwise linear regression analysis showed that fat free mass was the only significant determinant variable for REE (P ＜ 0.001 ). Conclusion Fat free mass is a factor than can influence the energy metabolism in patients with newly diagnosed esophageal cancer.