Background <p>Sodium benzoate, a common food preservative, may harm fetuses, which could increase the safety concern for pregnant women, but the knowledge, attitude, and practice (KAP) of food preservatives’ impact on health among pregnant women is limited. This study explored the KAP of pregnant women regarding food preservatives.</p> Methods <p>This cross-sectional study was conducted in Henan Province between March and April 2023 among pregnant women. An investigated-designed questionnaire was administered to collect the demographic characteristics and KAP scores. Scores of &lt; 60%, 60-79%, and <i>≥</i> 80% were considered poor, moderate, and good, respectively.</p> Results <p>The study collected 515 valid questionnaires [303 (58.83%) &lt; 30-years-old participants] for analysis. The knowledge, attitude, and practice scores were 10.21 ± 2.90 (/17; 60.06%), 29.59 ± 2.73 (/40; 73.98%), and 22.86 ± 3.56 (/30; 76.20%), respectively. The structural equation model (SEM) showed that the knowledge of food preservatives directly affected attitudes (β = 0.168, <i>P</i> = 0.005) and practice (β = 0.250, <i>P</i> = 0.021) and indirectly affected practice (β = 0.047, <i>P</i> = 0.004). The attitudes toward food preservatives directly affected practice (β = 0.280, <i>P</i> = 0.021).</p> Conclusion <p>Pregnant women in Henan Province have moderate knowledge, attitudes, and practices toward food preservatives. Education interventions are needed to improve the knowledge gaps identified in this study, which could also be encountered in other regions.</p> Trial registration <p>Not applicable.</p>