There is a lack of a good marker for early kidney injury in premature newborns. In recent publications, netrin-1 seems to be a promising biomarker of kidney damage in different pathological states. The study aimed to measure the urinary level of netrin-1 depending on gestational age. A prospective study involved 88 newborns (I-60 premature newborns, II-28 healthy term newborns). Additionally, premature babies were divided for 2 groups: IA-28 babies born between 30-34 weeks of gestation and IB-32 born at 35-36 weeks. The median urinary concentration of netrin-1 was: IA-(median, Q1-Q3) 63.65 (56.57-79.92) pg/dL, IB-61.90 (58.84-67.17) pg/dL, and II-60.37 (53.77-68.75) pg/dL, respectively. However urinary netrin-1 normalized by urinary concentration of creatinine were IA-547.9 (360.2-687.5) ng/mg cr., IB-163.64 (119.15-295.96) ng/mg cr., and II-81.37 (56.84-138.58) ng/mg cr., respectively and differ significantly between the examined groups (p = 0.00). The netrin-1/creatinine ratio is increased in premature babies. Further studies examining the potential factors influencing kidney function are necessary to confirm its potential value in the diagnosis of subclinical kidney damage in premature newborns.