Background: Institutionalization from birth offers a unique opportunity to investigate the effects on brain and endocrine system of psychosocial deprivation in early infancy. Nonetheless, a systematic review about institutionalization and biological anomalies does not exist. Objective: The purpose of this paper was to systematize all the studies about biological correlates of early institutionalization. Methods: GoogleScholar, PsycINFO, and PubMed electronic databases were used in order to select English language articles published on this topic. Reference lists of included studies were reviewed to capture additional studies. Only quantitative, peer reviewed studies, conducted on children and youths who had experienced institutional care from birth and assessing neurobiological features were included. Thirty-four studies met inclusion criteria. Results: The studies reported that the experience of institutionalization may lead to reduced brain volume, larger amygdala volume, decreased cortical activity, altered frontal and limbic activity, white matter abnormalities, and irregular hormone levels. These outcomes are similar to those displayed by children who have experienced harmful events. Although the body of literature is conspicuous enough to highlight anomalies in these children's neurobiology, only few studies specifically address each brain component or function. Conclusions: Adverse early experience can lead to aberrant brain development and functioning. Nevertheless, the comprehension of these neurobiological pathways requires further clarification.