Background: Balsalazide is an anti-infl ammatory drug used in the treatment of inflammatory bowel disease. Balsalazide can reduce inflammatory response through several mechanisms including inhibition of nuclear factor κB (NF-κB) activity. Parthenolide (PT), a NF-κB inhibitor, has recently been demonstrated as a promising anticancer agent that promotes apoptosis of cancer cells. Methods: In the present study, we investigated the antitumor effect of balsalazide combined with PT by significant inhibition of NF-κB on a human CRC cell line, HCT116. Results: The results demonstrated that combination of balsalazide and PT induced apoptosis which was determined using MTT, cell cycle analysis and annexin-V assay. Combination of balsalazide and PT markedly suppressed nuclear translocation of NF-κB subunit p65 and IκB- phosphorylation. Apoptosis through the mitochondrial pathway under NF-κB signaling was confirmed by detecting regulation of Bcl- 2 family members, cytochrome C release, and activation of caspase 3 and 8. Our data demonstrate that combination of balsalazide and PT inhibits synergistically cell growth and induces apoptotic cell death through blockade of NF-kB signaling pathway. Conclusions: This is the first evidence that combination of balsalazide and PT could be a new regimen for colorectal cancer treatment.