BACKGROUND: Intra ventricular hemorrhage (IVH) is a major cause of mortality among very low birth weight infants. This study aimed to investigate the relationship between mean platelet volume (MPV) and IVH in very low birth weight infants. METHOD: In this cohort study, all premature infants weighing less than 1500 grams who were admitted to the NICU were enrolled from August 2018 to July 2019. Brain ultrasonography was performed on the first and seventh days and one month of age and were compared with Platelet count and MPV. RESULTS: From 183 neonates, 23 cases (12.6%) had IVH. The mean MPV on the first day in the group with IVH was 10.48±0.85 and in the non-IVH group was 9.9±0.74 (P = 0.005). The mean MPV on the seventh day in the IVH and non-IVH group were 10.4±0.92 and 10.03±0.74 (P = 0.04) respectively. On the first and seventh day, for one unit of MPV increase, the chance of IVH increased by 2.68 and 2.1 respectively. (p = 0.001; OR3.643; 95% CI [1.703–7.753]). CONCLUSION: The mean MPV index is significantly higher in the infants with IVH and therefore it can be used in early detection of IVH in neonates weighing less than 1500 grams.