Objective: To investigate the clinical efficacy of postoperative chemotherapy combined with cytokine-induced killer cell (CIK) therapy in rectal cancer patients. Methods: The clinical data of 45 rectal cancer patients undergoing postoperative chemotherapy with FOLFOX4 regimen in combination with CIK therapy (CIK plus chemotherapy group) during June 2011 to May 2013 were retrospectively analyzed, and another 45 rectal cancer patients undergoing postoperative chemotherapy alone (chemotherapy alone group) with the same regimen during the same period served as control. The quality of life, short-term results, survival rate and adverse reactions between the two groups were compared, and the influential factors for prognosis of rectal cancer patients were also analyzed. Results: In CIK plus chemotherapy group compared with chemotherapy alone group, the improvement rate in quality of life was significantly increased (82.2% vs. 33.3%, P<0.05), the overall response rate had no significant difference (31.1% vs. 22.2%, P>0.05), but the disease control rate was significantly increased (77.8 % vs. 51.1%, P<0.05). The 1- and 2-year overall survival rate showed no significant difference (100.0% vs. 97.8%; 93.3% vs. 80%, both P>0.05), but the 1- and 2-year progression-free survival rate was significantly increased (86.7% vs. 62.2%; 62.2% vs. 40%, both P<0.05) and the overall incidence of adverse reactions showed no significant difference (46.7% vs. 53.3%, P>0.05). Univariate analysis showed that degree of tumor differentiation, lymph node metastasis, TNM stage and surgical procedure were associated with the prognosis of rectal cancer patients (all P<0.05), and multivariate analysis identified that degree of tumor differentiation and pathological stage were independent prognostic factors (both P<0.05). Conclusion: Postoperative chemotherapy in combination with CIK immunotherapy can significantly improve the quality of life, increase the overall efficacy, and prolong the progression-free survival rate of rectal cancer patients. The degree of tumor differentiation and pathological stage are independent postoperative prognostic factors for rectal cancer patients.