NF-κB interacting lncRNA (NKILA) has been found to function as a tumor-suppressive role in various human cancers. However, the role of NKILA in rectal cancer is still unknown. The objective of this study is to investigate the clinical value and biological function of NKILA in rectal cancer. The association between NKILA expression and clinical variables including prognosis was estimated in rectal cancer patients. The gain-of-function study of NKILA in rectal cancer cell was conducted to evaluate the effect of NKILA on cell proliferation, migration, invasion, and NF-κB signaling pathway. The results suggested NKILA expression was decreased in rectal cancer tissues and cells, and correlated with clinical stage, T classification, N classification and M classification. NKILA low-expression was an independent poor prognostic factor in rectal cancer patients. NKILA-inhibited rectal cancer cell proliferation, migration, and invasion via suppressing NF-κB signaling. In conclusion, NKILA serves as an antioncogenic lncRNA in rectal cancer.