Thus far, little is known about insulin action in the human brain. Nonetheless, recent advances in modern neuroimaging techniques, as functional magnetic resonance imaging (fMRI) or magnetoencephalography (MEG), have made it possible to investigate brain insulin action in humans providing new insights into the pathogenesis of brain insulin resistance and obesity. Using MEG, the clinical relevance of brain insulin action was first identified linking cerebral insulin resistance with peripheral insulin resistance, genetic predisposition and weight loss success in obese adults. While MEG is a suitable tool to measure brain activity mainly in cortical areas, fMRI provides high spatial resolution for cortical as well as subcortical regions. Thus insulin action can be detected within all eating behavior relevant regions, which include regions deeply located within the brain as the hypothalamus, midbrain and brainstem as well as regions within the striatum. In this review, we will outline recent advances in the field of neuroimaging to investigate insulin action in the human brain using different routes of insulin administration. fMRI studies have shown a significant insulin induced attenuation predominantly in occipital and prefrontal cortical regions and the hypothalamus, successfully localizing insulin sensitive brain regions in healthy mostly normal-weight individuals. However, further studies are needed to localize brain areas affected by insulin resistance in obese individuals, which is an important prerequisite to selectively target brain insulin resistance in obesity.