Preoperative functional status is a risk factor for developing postoperative complications (POC) in major abdominal and thoracic surgery, but this has hardly been evaluated in esophageal cancer patients undergoing esophagectomy. The aim of this prospective cohort study was to determine if preoperative functional status in esophageal cancer patients is associated with POC. From March 2012 to October 2014, esophageal cancer patients scheduled for esophagectomy at the outpatient clinic of a large tertiary referral center were eligible for the study. We measured inspiratory muscle strength, hand grip strength, physical activities, and health related quality of life as indicators of functional status one day before surgery. POC were scored according to the Clavien-Dindo Classification. We used univariate and multivariate backward regression analysis to determine the association between functional status and POC. We included 94 patients in the study and esophagectomy was performed in 90 patients from which 55 developed POC (61.1%). After multivariate analysis, none of the indicators of preoperative functional status were independently associated with POC (inspiratory muscle strength [OR 1.00; P = 0.779], hand grip strength [OR 0.99; P = 0.250], physical activities [OR 1.00; P = 0.174], and health related quality of life [OR 1.02; P = 0.222]). We concluded that preoperative functional status in our study cohort is not associated with POC after esophagectomy.