Oligodendrocytes provide support to axons by supplying lactate for aerobic ATP production, but the regulation of this process is unclear. Axons can release glutamate during phases of neuronal activity, and NMDA-type glutamate receptors (NMDARs) are found in oligodendrocytes, although the function of these receptors is not known. Here, glial NMDAR stimulation promoted glucose transporter 1 translocation to the plasma membrane, leading to increased oligodendrocytic glucose uptake and lactate release. This may allow oligodendrocytes to meet the metabolic demands of active axons without developing damagingly high internal levels of lactate.