Cerebral blood flow is altered in migraineurs but it is unknown if this can be changed by repetitive neurostimulation, leading to less migraine attacks. In a double blind and sham-controlled study, we used arterial spin labeling MRI and transcranial direct current stimulation (tDCS) to address this question. Four weeks of real tDCS diminished initial hyperperfusion in patients with episodic migraine in pain processing brain regions (p < 0.001). In addition, less migraine attacks occurred after real tDCS compared to baseline (p < 0.05). Our results indicate a regulating effect of tDCS on cerebral blood flow and clinical outcome in migraineurs.