The aim of this retrospective study was to assess the need for additional enteral protein supplementation in preterm newborns with gestational age (GA) ≤32 weeks after full enteral feeds with either fortified breast milk (FBM) or preterm formula (PF) were reached, and to determine the effects of additional protein on physical and neurological development. After the standard early total parenteral nutrition (TPN) and reaching full enteral nutrition with 150-160 ml/kg/day, preterms were assessed for the requirement of additional protein based on serum blood urea nitrogen (BUN)/prealbumin levels. Additional enteral protein was given for BUN <5 mg/dl and/or prealbumin ≤8 mg/dl with weekly assessments as per Neonatal Intensive Care Unit (NICU) protocol. Growth in the NICU and neurodevelopmental outcome at 18 months' corrected age (CA) were determined. There were 32 newborns in the non-supplemented group (Group 1) and 33 newborns in the supplemented group (Group 2). All newborns in Group 2 were on FBM. Weight gain and head growth were better and Bayley scores at 18 months' CA were higher in Group 2. Standard preterm nutrition with FBM may not be sufficient for preterms, and additional enteral protein supplementation may improve the physical growth rate in the NICU and result in better neurodevelopmental outcome at 18 months' CA.