Introduction: Vitamin D is a potent regulator of placental immunity, stimulating antimicrobial response, which suppresses inflammation. Studies have shown an association between reduced level of maternal serum vitamin D and preterm delivery. This study will contribute to further establishing the association between maternal serum vitamin D levels and preterm delivery, especially in our environment and provide data to prevent preterm delivery. Objective: The aim of this study was to determine the levels of serum vitamin D in women with preterm deliveries and to compare this with women with normal term deliveries at the Lagos University Teaching Hospital (LUTH) Study design: This was a cross sectional comparative study of two groups of women with preterm and term deliveries respectively. Two hundred and six women were recruited for this study. This comprised of 103 women with preterm delivery and 103 women with normal term deliveries. With a structured pro-forma, socio-demographic information was obtained, as well as information about the duration of daytime spent outdoors, dressing style and the type of patients skin complexion. Maternal venous blood samples were collected immediately after delivery. Serum level of 25(OH)D was determined using the CALBIOTECH Vitamin D ELISA kit according to the kit’s instructions. Data were analyzed using SPSS version 20 statistical software package.