Introduction: Parenteral nutrition (NPT) support is another option in newborn when they cannot receive enteral nutrition. Thrombocytopenia has been reported as a complication for the use of NPT intravenous lipids. Objective: To evaluate the effect of NPT intravenous lipids on platelet blood counting in newborns. Materials and methods: this is a prospective study carried out in newborns requiring parenteral nutrition support who were hospitalized in BucaramangaColombia. All patients received intravenous lipids. Doses were increasing of 0,5 g/kg/ day at the first day to reach 3 g/kg/day at the end. They were monitored daily and platelet blood counting was assessed at baseline and seven days later. Results: subjects were 22 term newborns and 29 preterm (55% men), they presenting different clinical conditions like prematurity (22), necrotic enterocolitis (17), respiratory problems (4), esophageal atresia (2) and others (6). The platelet blood counting showed no significant differences between baseline and the seventh day (p> 0.05), no in preterm (227.320±86290/mm3 versus 294.930±120.600/mm3),and either in the newborns (276.140±130.240/mm3 versus 273.240±96.890/mm3) no adverse effects were reported. Conclusion: administration of intravenous lipid at doses up to 3 g/ kg / day in term and preterm newborns is safe, and no thrombocytopenia was not reported and other adverse effects.