Inhibitor of nuclear factor kappa B kinase subunit B (IKBKB or IKKβ) is a key activator of the nuclear factor κB transcription factor pathway. Increased expression and/or aberrant activity of IKBKB have been observed in various types of human cancer. Three independent techniques, reverse transcription‑quantitative polymerase chain reaction, western blotting and immunohistochemistry, were used to demonstrate that IKBKB expression is decreased in clear cell renal cell carcinoma (ccRCC). Notably, the patients with upregulated IKBKB protein expression were characterized by higher nuclear grade tumors and significantly shorter survival. The findings indicate that IKBKB protein may be of clinical relevance in ccRCC, serving as a marker of poor prognosis and as potential target for adjuvant chemotherapies. Further studies are required to validate the prognostic and predictive value of IKBKB.