Mother-child human leukocyte antigen (HLA)diversity is protective for vertical transmission of some viruses. The aim of this study is to evaluate the role of mother-child HLA diversity on hepatitis C virus (HCV) vertical transmission. Forty consecutive HCV infected and 46 consecutive control uninfected children born to HCV-RNA positive mothers were evaluated for HLA class-1 type concordance with their mothers. No significant difference in the degree of HLA concordance was found between HCV infected and uninfected children both when A, B, C (p=0.30) and when only A and B alleles were evaluated (p=0.59). Mother-infant HLA concordance does not affect HCV vertical transmission.