Aim: To investigate the correlation between acute respiratory distress syndrome (ARDS) and serum 25(OH) vitamin D3 levels in pediatric patients. Material and methods: This prospective study included the enrolment of all preterm infants with a gestational age of 32 weeks or less who were admitted to the neonatal intensive care unit (NICU) at our hospital. The diagnosis of RDS was established through the assessment of both radiographic and clinical findings. The utilization of maternal 25-hydroxyvitamin D (25(OH)D) was categorized into three distinct groups.Blood samples from neonatal intensive care unit (NICU) patients were acquired within six hours after birth, while maternal blood samples were collected within the initial four hours following birth. The plasma derived from blood samples obtained from both the infants and mothers was stored at a temperature of -80°C. The samples underwent analysis utilizing a Shimadzu LC-20AT high-performance liquid chromatography system, which was equipped with a UV detector. Results: Out of the 100 participants enrolled in the study, respiratory distress syndrome (RDS) was detected in 70 individuals, while the remaining 30 participants did not exhibit any signs of RDS. The levels of 25(OH)D were found to be 7.33 ng/mL in the group with respiratory distress syndrome (RDS) and 10.01 ng/mL in the group without RDS. A statistically significant difference in the levels of 25(OH)D was observed between the two groups (p=0.03). There was no statistically significant correlation observed between maternal vitamin D levels and the development of respiratory distress syndrome (RDS). However, it is worth mentioning that the incidence of RDS in group 1, which consisted of patients with severe 25(OH)D deficiency, was higher at 85.71% . Conclusion: The deficiency of 25-hydroxyvitamin D (25(OH)D) is an autonomous risk factor for the development of respiratory distress syndrome (RDS) in premature infants. Conversely, elevated levels of 25(OH)D in neonates at birth may serve as a protective factor against RDS in premature infants.