The objective of this study was to measure lutein and zeaxanthin plasma levels after oral lutein administration in preterm infants. Lutein was given orally in a single dose of 0.5 mg/kg to 10 preterm infants at a mean age of 52 h of life. Plasma lutein and zeaxanthin were measured before and 6, 24, 48, and 120 h after lutein administration. All infants had detectable plasma levels of lutein and zeaxanthin before treatment. Lutein concentration increased by 13.5% at 6 h and by 16.7% at 24 h, and returned to the basal level at 120 h after treatment. Zeaxanthin remained unchanged during the study period. Lutein is well absorbed in preterm infants when given orally. The clinical impact of increasing plasma lutein concentrations on macular development and visual function needs further investigation.