Reduced fetal growth is associated with increased systolic blood pressure. Recently, we found an inverse association between serum ω-3 fatty acids and systolic blood pressure in young adults born with impaired fetal growth. We investigated the associations of dietary intake in childhood of the long-chain ω-3 fatty acids eicosapentaenoic acid and docosahexaenoic acid with blood pressure parameters in children born with reduced birth weight. We analyzed data from 3457 children aged 8 to 15 years participating in the continuous National Health and Nutrition Examination Survey 2003-2004, 2005-2006, and 2007-2008. Dietary intake was assessed by two 24-hour dietary recalls, birth weight by questionnaire, and blood pressure was measured. Systolic blood pressure was 1.1 mm Hg higher in those with reduced (<10th centile) compared with normal birth weight (≥ 10th centile), consistent with previous findings, although not statistically significant (P=0.40); however, pulse pressure was significantly higher in these children (3.4 mm Hg). In the 354 participants with reduced birth weight, when compared with children with the lowest tertile of intake, those who had the highest tertile of dietary eicosapentaenoic acid and docosahexaenoic acid intake had significantly lower systolic blood pressure (-4.9 mm Hg [95% confidence interval, -9.7 to -0.1]) and pulse pressure (-7.7 mm Hg [95% confidence interval, -15.0 to -0.4]). High-dietary intakes of eicosapentaenoic acid and docosahexaenoic acid are associated with lower systolic blood pressure and pulse pressure in children born with reduced birth weight. These data are consistent with the hypothesis that long-chain ω-3 fatty acids reduce blood pressure in those with impaired fetal growth.