This study evaluated the effect of supplementation of rumen-protected (RP) lysine, AjiPro-L (Ajinomoto Co. Inc., Tokyo), during the close-up dry period on nutrient metabolism and lactaion performance in early lactating cows. Twenty pregnant Holstein dairy cows (8 primiparous and 12 multiparous) were housed in individual stalls during the last 21 d of gestation. From 21 d before expecting calving to parturition, cows were blocked by parity and randomly assigned 1 of the following 2 treatments: (1) control diet [CP: 13.3% of DM, NE_L: 1.36 kcal/g of DM, metabolizable lysine: 81 g/d; Con]; (2) RP lysine supply for control diet [metabolizable lysine: 97g/d; Lys]. After calving, all cows were managed in freestall barns; TMR was provided 3 times daily and milking done twice daily. Blood samples were collected from the jugular vein at −21, −14, 0 (calving date), 7, 21, and 35 d. A mixed model was used to determine the effects of treatment and time as repeated measures, and their interaction. Dry matter intake (DMI) was higher for Lys (12.4 kg/d; LSM) than for Con (10.4 kg/d), during the prepartum period (P = 0.03). After calving, DMI tended to be higher for Lys (14.5 kg/d) than for Con (11.6 kg/d) during the first 21 d. In addition, milk yield tended to be greater for Lys (27.9 kg/d) than for Con (24.2 kg/d). Milk fat and lactose yield were greater for Lys (1.46, 1.41 kg/d) than for Con (1.17, 1.19 kg/d), respectively (P = 0.02). Furthermore, liver functionality index, (calculated using plasma concentrations of albumin, cholesterol and bilirubin) tended to be higher for Lys than for Con after calving (P = 0.08), whereas plasma hormone concentrations (ghrelin, insulin-like growth factor 1, growth hormone, glucagon and insulin) did not differ between treatment groups. In conclusion, RP lysine supplementation during the close-up dry period increased DMI in the peripartum period, resulting in enhanced lactating performance, and may offer benefits in terms of liver functionality in early lactating cows.