Background: Tobacco-related health literacy is a skill for pregnant women that leads to a correct understanding of the information needed to maintain the health of the fetuses and themselves against tobacco smoke. Cultural capital is also associated with the capacity and ability to acquire skills. Objectives: This study aimed to investigate pregnant women's cultural capital and tobacco-related health literacy and the relationship with fetal smoke exposure. Methods: This cross-sectional study recruited a sample of 500 pregnant women referred to hospitals affiliated with Tehran University of Medical Sciences. The data were gathered using a researcher-made questionnaire. Results: Tobacco-related health literacy was 60.8% more common at the high level. The cultural capital of pregnant women was 81.4% higher in the medium level. Logistic regression showed that cultural capital (OR = 0.47 and B = -0.737) and tobacco-related health literacy (OR = 0.77 and B = -0.0257) reversely affected the fetal tobacco smoke exposure (P < 0.05). As women's tobacco-related health literacy and cultural capital increased, the rate of fetal smoke exposure decreased. Conclusions: According to the results, as pregnant women’s health literacy concerning tobacco smoke and their cultural capital increased, the tobacco smoke exposure of pregnant women and their fetuses decreased.