Identifying patients with a genetic predisposition for developing malignant tumors has a significant impact on both the patient and family. Recognition of genetic predisposition, before diagnosing a malignant pathology, may lead to early diagnosis of a neoplasia. Recognition of a genetic predisposition syndrome after the diagnosis of neoplasia can result in a change of treatment plan, a specific follow-up of adverse treatment effects and, of course, a long-term follow-up focusing on the early detection of a second neoplasia. Responsible for genetic syndromes that predispose individuals to malignant pathology are germline mutations. These mutations are present in all cellsof conception, they can be inherited or can occur de novo. Several mechanisms of inheritance are described: Mendelian autosomal dominant, Mendelian autosomal recessive, X-linked patterns, constitutional chromosomal abnormality and non-Mendelian inheritance. In the following review we will present the most important genetic syndromes in pediatric oncology.