Objectives: This study was to determine the correlation of neonatal birth weight, crown heel length, head circumference, chest circumference and foot length with the gestational age calculated by New Ballard Score. And to determine the correlation of neonatal foot length with the birth weight of the baby in a tertiary care hospital of Eastern Bihar. Methods: Anthropometry examinations like birth weight, Head Circumference (HC), Chest Circumference (CC) and Crown Heel Length (CHL) and Foot Length (FL) were measured by using standard techniques. The New Ballard Score was used for gestational age which included Neuromuscular assessment, physical maturity, genital examinations and expected date of delivery, gestational age, birth weight were performed. Results: Data was analysed by using IBM SPSS version 22 statistical analysis software. Independent sample t–test (2 groups) / ANOVA and Chi square test /Fisher‘s Exact test were applied. Mean ± standard deviations were observed. P– value was taken less than or equal to 0.05 (p≤0.05) for significant differences. Conclusions: This study concluded that the foot length, chest circumference, crown heel length and head circumference were positively correlated with the gestational age and birth weight. And foot length had the highest sensitivity (98%) and specificity (97.96%) for the detection prematurity.