The English and Romanian Adoptees Brain Imaging Study investigates the effects of early institutional deprivation on brain structure in young adulthood. This study analysed MRI data of young adults, who were exposed to severe deprivation in early childhood in the Romanian orphanages of the Ceaușescu era before being adopted by UK families. This dataset contains brain structural summary data of 67 Romanian adoptees and 21 non-deprived UK adoptees. Additionally, this dataset contains information on neurodevelopmental symptom domains, deprivation duration, birth weight, weight at entry into the UK and polygenic scores for total brain volume.