Objective To investigate the voiding pattern in preterm neonates affected by hypoxic-ischemic encephalopathy (HIE).Methods A total of 81 preterm newborns aged 4 to 15 days at The First Affiliated Hospital of Zhengzhou University from March to October 2010 were included in this study,48 of them affected by HIE (32.1 ± 0.7 weeks of gestation) with weight of 2.5 ± 0.3 kg,the other 33 preterm were normal (32.3 ± 1.4) weeks of gestation,body weight: 2.4 ± 0.5 kg).The voided volume,post void residual (PVR) volume,voiding frequency per 4 hours as well as the quantity of milk and liquid intake within the same time schedule for 4 hours from 8AM to 12AM were recorded.The liquid intake was given according to standard protocol.Results A total of 248 times of voiding were recorded.Voided volume and bladder empty percentage was significant lower in newborn with HIE comparing to controls [(14.4 ± 8.3) ml vs.(16.5 ± 9.2) ml and 11.6％ vs.24.3％,(P＜0.05),respectively],whereas voiding frequency,PVR volume showed no significant difference.Conclusions The difference of voiding patterns between newborn with HIE and controls indicates HIE has a significant effect on the bladder storage and voiding function.