OBJECTIVE To investigate the distribution of killer cell immunoglobulin-like receptors (KIR) and their specific ligands human leukocyte antigen-I (HLA-I) gene in northern China. METHODS One hundred and eighty-four unrelated northern Chinese Han individuals were recruited. Genotypes of the KIR and HLA-ABC genes were studied by sequence-specific primer polymerase chain reaction (SSP-PCR). RESULTS Sixteen KIR genes were detected among the 184 unrelated individuals. In all individuals, the four framework genes were present. The frequencies for those carrying the remaining 12 KIR genes have ranged from 16.3% to 99.5%. Twenty-four KIR genotypes were identified, for which half were detected in a single individual. A new genotype comprised of KIR2DL3, 3DL1, 2DP1 and the framework genes was detected in one subject. Respectively, 12, 27 and 11 specificities of HLA alleles were identified on the HLA-A, B, C loci. CONCLUSION The distribution of polymorphisms of KIR and its ligand HLA-ABC genes among northern Chinese Han population have been ascertained. The frequencies of 9 KIR/HLA combinations in the above population have been determined for the first time.