This retrospective cohort study aimed to evaluate neurodevelopmental outcomes of preterm infants (≤ 34 weeks gestational age) in the NICU. This retrospective cohort study included 89 preterm infants admitted to the NICU of Ghaem hospital, Mashhad, between 2016 and 2020. Data on neonatal and maternal factors were collected. By recalling the mentioned infants in 2021, the neurodevelopmental outcomes were assessed using the Bayley Scales of Infant and Toddler Development. Data analysis included descriptive statistics, non-parametric tests, and binary logistic regression conducted with SPSS V.26 and R program software. The sample comprised 48.3 % males with a mean gestational age of 32.10 weeks. Bayley Scale analysis revealed significant associations of Intrauterine Growth Restriction, Pneumothorax, and Bronchopulmonary Dysplasia with impairments in all domains. Diabetes in Pregnancy, Surfactant use, and Necrotizing Enterocolitis were also significantly linked to various impairments. Lower Apgar scores, gestational age, birth weight, and extended hospitalization and oxygen therapy durations correlated with several domain impairments. Logistic regression showed hospitalization duration impacted the coarse motor domain (OR = 0.92, p = 0.019), oxygen therapy duration influenced cognitive, perceptual, and fine motor domains. This study underscores the importance of considering neonatal and maternal factors when assessing developmental outcomes in preterm infant. Long hospital stays and increase duration of oxygen therapy associated with negative developmental outcomes in different domains of Bayley scales. Early identification of these risk factors and targeted interventions may improve long-term outcomes for preterm children.