We evaluated the relationship between the dietary intake of vegetables and fruits, and the risk of cervical intraepithelial neoplasia (CIN) and determined whether these associations were modified by human papillomavirus (HPV) viral load. We enrolled 1,096 women aged 18-65 to participate in a HPV cohort study from March 2006 up to present. For this analysis, we included 328 HPV-positive women (166 controls, 90 CIN I and 72 CIN II/III). The multivariate odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were estimated by multinomial logistic methods. After controlling for potential confounders, we found that a higher HPV viral load was associated with an increased risk of CIN I (OR = 2.68, 95% CI, 1.19-6.04) and CIN II/III (OR = 2.78, 95% CI, 1.15-6.72). The relationships between HPV infection, dietary intake of vegetables and fruits and risk of CIN were not statistically significant. However, subjects with lower intake of vegetables and fruits, and a higher viral load (> or =15.5) have a higher risk of CIN II/III (OR = 2.84(1.26-6.42), interaction p = 0.06 for vegetables; OR = 2.93(1.25-6.87), interaction p = 0.01 for fruits), compared with subjects with lower intake of vegetables and fruits, and a lower viral load (<15.5). Our findings suggest that the dietary intake of vegetables and fruits is associated with the progression of cervical carcinogenesis.