Leukemia is defined as an aberrant hyper-proliferation of immature blood cells that do not form solid tumor masses (i.e., liquid cancer). Usually, leukemia could be either of the myeloid or lymphoid lineages, and is classified as acute or chronic in nature. Chronic leukemias tend to have more mature cells and are rare in pediatric patients. Acute leukemias, on the other hand, are typically less mature and commonly occur in patients of all ages and are potentially rapidly fatal if not readily treated. The acute lymphoblastic leukemia (ALL) is the most common childhood malignancy. Similar to AML, and in some cases, on the same disease spectrum, are the myelodysplastic syndromes (MDS). The present review is focused on the recent perspectives of pediatric leukemia.