Background: Preterm labor remains a leading cause of neonatal morbidity and mortality worldwide. Emerging evidence suggests that maternal iron status, particularly elevated serum ferritin levels, may be associated with preterm labor through mechanisms involving inflammation or oxidative stress. Methods: This case-control study was conducted at the Department of Obstetrics & Gynaecology, Dhaka Medical College Hospital, from June 2022 to May 2023. A total of 88 pregnant women were enrolled, with 44 cases in the preterm labor group and 44 in the term labor (control) group. Maternal serum ferritin levels were measured and compared between the two groups. Sociodemographic and obstetric data were also analyzed. Statistical significance was determined using appropriate tests, with a p-value < 0.05 considered significant. Results: The mean maternal age was 25.59 ± 5.80 years in the preterm labor group and 24.56 ± 5.41 years in the term group (p = 0.076). A higher proportion of preterm labor cases were multiparous (59.1%), whereas most term deliveries were in primiparous women (52.3%), though this was not statistically significant (p = 0.285). Serum ferritin levels were significantly elevated in the preterm labor group (89.09 ± 106.07 ng/mL) compared to the term group (32.13 ± 31.40 ng/mL), with a p-value of 0.004. A significant negative correlation was found between ferritin levels and gestational age (r = -0.313, p < 0.05). Conclusion: Elevated maternal serum ferritin levels are significantly associated with preterm labor and inversely correlated with gestational age. Serum ferritin may serve as a potential biomarker for identifying women at risk of preterm delivery.