The concept of pediatric chemobrain and the neural mechanisms that underlie its development have not been adequately studied. In this study, MRI was used to examine the neuroanatomy of childhood cancer survivors. We found reduced brain volumes and cortical thicknesses in childhood cancer survivors compared to age-matched controls. These changes were in regions known to be involved in working-memory function and executive function, which could account for the development of executive function difficulties observed in childhood cancer survivors. These findings may prove useful to inform treatment strategies and modify behavioral programs to help survivors combat these issues.