We investigated the association between the interleukin 6 (IL-6)-174-genotype and unfavorable outcomes in preterm infants since it has been reported that the IL-6-174GG-genotype is associated with increased susceptibility to sepsis, and the IL-6-174CC-genotype is more common in preterm infants with severe intraventricular hemorrhage (IVH). We studied 1206 preterm infants with a birth weight below 1500 g. In contrast to previously published data, the frequency of IVH grade IV, periventricular leukomalacia, ventricular-peritoneal-shunting or death was not different between infants with different IL-6-genotypes: IL-6-174GG (n = 430) 8%, IL-6-174GC (n = 605) 9% and IL-6-174CC (n = 167) 12% (P = 0.2 for IL-6-174CC vs GG + GC). Furthermore, we were not able to confirm previously reported association between sepsis and the IL-6-174GG-genotype. Blood-culture-proven sepsis occurred in 19% of IL-6-174GG-carriers (n = 157), 26% of IL-6-174GC-carriers (n = 193) and 27% of infants carrying the IL-6-174CC-genotype (n = 67). We were not able to confirm previously reported associations between sepsis, cerebral injury and the IL-6-174-genotype in VLBW-infants.