Recent studies in non-ruminants have revealed that mammalian target of rapamycin (mTOR) signaling pathway plays a critical role in the regulation of adipose tissue function. The objective of the current study was to investigate whether increasing the methionine supply would alter mRNA expression of amino acid transporters and mTOR pathway components in adipose tissue during the periparturient period. Sixty multiparous Holstein cows were used in a block design and assigned to a control diet or the control plus rumen-protected methionine (MET; Mepron, Evonik Nutrition & Care GmbH, Germany). Mepron was fed from −28 to 30 d relative to parturition at 0.09% and 0.10% of the diet dry matter during the prepartum and postpartum period, respectively. Blood sampled from the coccygeal vessel at −14, 7, and 30 d relative to calving date was used for amino acid analysis. Adipose tissue obtained from each group on d −10, 10 and 30 relative to calving date was used for RT-PCR analysis. The statistical model included the random effect of block and fixed effect of treatment, time and its interaction. A treatment × time was observed for the plasma concentrations of Asn, Cys, and Gly due to higher responses in MET-supplemented cows (P < 0.05). Compared with control, MET-fed cows had greater concentration of Met, Lys, Thr, Leu, Val, and Phe in plasma (P < 0.05). Among the 7 amino acid transporters measured, MET-supply increased the mRNA expression of Gln (SLC38A1), Glu (SLC1A1), L-type amino acid (Met, Leu, Val, Phe; SLC3A2), small zwitterionic α-amino acid (SLC36A1), and neutral amino acid (SLC1A5) transporters in adipose tissue (P < 0.05). Expression of AKT1, RPS6KB1, and EIF4EBP1 were also upregulated in MET-supplemented cows in adipose tissue (P < 0.05), suggesting enhanced insulin signaling and activation of the mTOR pathway. Overall, the data indicate that enhanced methionine supply during the periparturient period enhances circulating amino acid concentrations and the availability and uptake of amino acids by adipose tissue.