Positional plagiocephaly is an asymmetrical skull deformation caused by various factors. Although it is not responsible for abnormal brain development in infants and is not related to the onset of neurophysiological problems, it is critical to prevent skull deformity to avoid aesthetic and functional consequences. The purpose of the study is to investigate the relevance of preventive procedures to the onset of positional plagiocephaly, such as the use of passive mattresses, which is primarily correlated with the need for newborns and infants to sleep and rest in proper posture. PubMed, Web of Science, Google Scholar, Scopus, Cochrane Library, and Embase were searched for papers that matched our topic, dating from January 2012 to 22 October 2022, with an English language restriction, using the following Boolean keywords: (“positional plagiocephaly” AND “prevention”). A total of 11 papers were included as relevant papers matching the purpose of our investigation. According to the research results, inadequate vitamin D and folic acid intake during pregnancy may increase the risk of skull deformation. Furthermore, babies should sleep on their backs and spend at least 30 min in tummy time. Using a passive sleep curve mattress has several advantages such as low cost, easy handling, no compliance system, and a marked improvement in head shape, allowing harmonious skull growth guided by normal brain expansion.