This study used voxel-based morphometry method to examine gray matter volume alterations related to impulsive personality traits in obese individuals relative to controls. 62 adolescents completed the UPPS-P Impulsive Behavior Scale were analyzed. Possible GM volume alterations were firstly analyzed at the whole brain range. The relationship of regional GM volumes with UPPS-P scores were examined in selective regions of interest. This study demonstrated that sensation seeking behavior in obese people negatively correlate with GM volumes of amygdala, OFC, hippocampus, and insula indicate high sensitivity to food cues in adult obesity that link to certain alternations of the brain structure.