Activated nuclear factor-κB (NF-κB) is associated with the pathogenesis of numerous cancers, such as gastric cancer (GC). Genetic polymorphisms in the genomic region containing nuclear factor-κB1 (NFKB1) have a plausible role in modulating the risk of GC. To identify markers contributing to the genetic susceptibility to GC, we analyzed 15 single nucleotide polymorphisms (SNPs, rs28362491, rs3774932, rs1598856, rs230531, rs230530, rs230528, rs230521, rs230498, rs230539, rs1005819, rs3774956, rs4648055, rs3774964, rs4648068, and rs3774968) in the genomic region containing NFKB1. The participants included 401 patients with GC and 433 healthy controls. The allelic or genotypic frequencies of the rs28362491 (located in the promoter region of NFKB1), rs230521 (NFKB1 intron 4), and rs4648068 (NFKB1 intron 12) polymorphisms in the patients with GC were significantly different from those in the healthy controls. Strong linkage disequilibrium was observed in 4 blocks (D'>0.9). Significantly more A-T haplotypes (block 1, P=0.0005), A-C haplotypes (block 2, P=0.0001) and G-A-A haplotypes (block 4, P=0.016) were found in the patients with GC. Significantly more A-C haplotypes (block 1, P=0.005) and A-G haplotypes (block 2, P=0.0004) were found in the healthy controls. These findings suggest a role for NFKB1 polymorphism in GC among a Han Chinese population and may be informative for future genetic studies on gastric cancer.