Recent research suggests an impact of psychological distress on postoperative outcomes in orthopedic and neurosurgery. It is widely unknown whether patients’ mood might affect the postoperative outcome and complication rate in colorectal surgery. Over a period of 22 months, a monocentric, observational study among patients undergoing elective colorectal surgery without the creation of an ostomy was conducted. Patients were asked to fill in a standardized multi-dimensional mood questionnaire (MDMQ) preoperatively as well as on the third, sixth, and ninth postoperative days to assess mood, wakefulness, and arousal. The results of 80 patients (51% male, mean age 59 years) were analyzed. Almost half of the patients (58%) developed postoperative complications according to the Clavien–Dindo classification (Grade I 14%, Grade II 30%, Grade III 9%, Grade IV 3%). Patients’ mood increased continually from the preoperative day to the ninth postoperative day. Patients’ wakefulness decreased initially (pre- to third postoperative day) and increased again in the further course. Patients’ arousal decreased pre- to postoperatively. Neither preoperative mood, nor arousal or wakefulness of patients showed a clear association with the development of postoperative complications. In conclusion, preoperative psychological distress measured by MDMQ did not affect the postoperative complication rate of patients undergoing elective colorectal surgery.