Objective: Troponin is an inhibitory protein complex located on the actin flament in all striated muscles. Cardiac Troponin I is found only in the heart and has been used as a sensitive and specific marker of myocardial injury. Our aim was to investigate the different percentile limits and determinants of cord blood cardiac Troponin I (Tn I) concentrations. Material and Methods: A total of 378 consecutive healthy neonates were included in the study. Umbilical cord arterial and venous blood samples were obtained at the time of delivery. Concentrations and determinants of cardiac Tn I were analyzed using multivariate analysis, and percentile values were calculated. Results: Multivariate analyses showed that gestational age in weeks (B= -0.17, p= 0.02, t= -2.3) and fetal gender (B= -0.11, p=0.03, t= -2.08) were independent determinants of cord blood cardiac Tn I concentrations. The cases were divided into term 07 weeks of gestation) and pretem (<37 weeks of gestation) subgroups for the ease of clinical evaluation. The demographic variables of mothers of term and preterm infants were similar (p> 0.05) except for gestational age (p< 0.01). Mothers of preterm cases had significantly more frequent tocolytic therapy, early rupture of membranes, hypertension and cesarean delivery (p< 0.01). Term infants had more frequent labor induction and labor augmentation (p< 0.01). The 99th percentile limits of cardiac Tn I were 3.8 ng/ml in male (n= 47) and 0.8 ng/ml in female (n= 32) for pre-terms. In term neonates, these values were 2.7 ng/ml in males (n= 166) and 3.1 ng/ml in females (n= 133). Conclusion: This study reports the different cardiac Tn I percentile limits in a neonatal population. Our results suggested that the upper reference limits for cardiac Tn I may vary according to gestational age and gender.