Human leukocyte antigen-G (HLA-G) expression in 55 cervical intraepithelial neoplasia (CIN) patients with or without human papillomavirus (HPV) infection and 116 patients with squamous cell cervical cancer were examined using immunohistochemistry. Host immune response was assessed by estimating the number of intratumoral lymphocyte infiltration (TIL) in all lesions and counting CD57-expressing cells in the neoplasm lesions. The means of HLA-G immunoreactive scores were compared by the Mann-Whitney test and 1-way analysis of variance (ANOVA). The association of HLA-G expression with disease progression, HPV infection and host immune response was calculated using the Pearson Chi-square test. It was found that HLA-G expression increasingly progressed from patients with CIN 1 to CIN 2/3 and was highest in patients with cervical cancer. Human leukocyte antigen-G expression was also significantly higher in CIN and cancer patients with HPV 16/18 than in CIN patients without HPV. A significant correlation between HLA-G expression and TIL score or the counting of CD57-expressing cells was also evident in CIN patients with HPV infection and cervical cancer cases. These results suggest that HLA-G expression in cervical lesions is associated with carcinogenesis, HPV infection, and host immune response.