The longitudinal change of vitamin A concentration and secretion in transitional milk of 32 Korean lactating wormen and vitamin A intake of infants were studied 7, 10 and 15 days postpartum. Retinol concentration of the milk averaged 93.6$pm$47.1, 80.1$pm$41.6 and 66.7$pm$33.5$mu extrm{g}$/100ml at 7, 10 and 15 days postpartum respectively and showed decreasing trend in total mothers. $eta$-carotene concentration showed similar decreasing trend averaged 13.4$pm$10.6, 8.2$pm$4.6 and 5.3$pm$3.4$mu extrm{g}$/100ml respectively. Vitamin A concentration decreased with the respective amount of 94.9$pm$47.1, 80.5$pm$41.5 and 67.3$pm$33.0 R.E../100ml during the lactation. The average vitamin A secretion in the milk of all mothers appeared 410.0 R.E/day. Vitamin A secretion of multiparae (450.1 R.E./100ml) appeared not significantly higher than those of primiparae(370.0 R.E./100ml). The average vitamin A intake of infants in the milk averaged 333.7 R.E./day and was 95.3% of RDA for infants. Vitamin A intake per body weight of infants in the milk averaged 110.6, 91.9 and 79.2 R.E./kg/day respectively.