Global fluctuations of arterial spin labeling (ASL) signals may emerge from global synchronization of resting-state brain networks. We aimed to investigate the synchrony of ASL global signal with brain neural activity using simultaneously recorded ASL perfusion images and EEG. The correlation between the EEG frequency power time series and ASL global time courses was evaluated. The shape for time course of the correlation is very similar to hemodynamic response functional curve. The peak correlation time indicates that the global ASL signals follow the neural activity and the function of human brain is organized by the presence of global functional synchronization.