Background: Food security status is an important indicator for measuring the level of individuals' access to sufficient and nutritious food. This study was conducted to investigating the food security status in pregnant women in Yazd, Iran. Methods: In this cross-sectional study, 351 pregnant women with gestational age of 24 to 32 weeks were randomly selected. Food security status was measured by household food insecurity access scale (HAFIS) questionnaire. Demographic information was extracted from the health records of mothers. The data were analyzed using logistic regression test. Results: The mean age of studied women was 27.84 ± 5.46 years and the mean of their food security score was 3.45 ± 4.40. Food secure, marginal insecurity, and severe insecurity were observed in 45.6, 39, and 15.4 percent of participants, respectively. Socioeconomic status (SES) and non-Persian ethnicity had a significant relationship (P = 0.40) with food insecurity. Logistic regression analysis showed that the odds ratio of severe food insecurity in the low SES was 13 times higher than its odds in the high SES. The odds ratio of severe food insecurity for non-Persian was also 6 times higher than its odds for Persian people. Conclusion: More than half of the pregnant women were in the mild to severe range of food insecurity and the prevalence of this situation was higher in women with low social economic status and non-native groups.