W9 is a Boreal forest plant identified among species used by the Cree of Eeyou Istchee of northern Quebec to treat symptoms of diabetes. In a previous study, the ethanol extract of W9 enhanced glucose uptake in C2C12 muscle cells via stimulation of AMP-activated protein kinase (AMPK) pathway. In this study, we investigated the effect of this product on the translocation of insulin-sensitive GLUT4 transporters in skeletal muscle cells in culture. Treatment of L6 myotubes with W9 for 18h significantly increased glucose uptake and GLUT4 translocation to the cell membrane. W9 increased phosphorylation of AMPK and P38 MAPK with no indication of increased phosphorylation of Akt. To validate the effect of W9 in vivo, the extract (1% in drinking water) was administered to KKAy diabetic mice for 10 days. Glycemia and fluid intakes were significantly reduced by W9. Moreover, W9-treatment increased skeletal muscle GLUT4 content, stimulated ACC phosphorylation and increased hepatic levels of PPAR-α of KKAy mice. Administration of W9 to normal C57BL/6 had no effect on glycemia. The results of the present study expand the understanding of the molecular mechanisms underlying the antidiabetic potential of W9.