Compared with acute B lymphoblastic leukemia (B-ALL) in children, the prognosis of T-ALL in children is poorer. It is easier to induce chemotherapy failure and recur early than B-ALL.If recur,T-ALL is difficult to relieve again. In recent years, the prognosis of children with T-ALL has improved.The 5-year event-free survival rate (EFS) reported by some foreign research centers can reach 85%.But most of the research centers remain at around 60%. Understanding the progress of T-ALL is particularly important for the diagnosis and treatment of the disease.The article reviews the progress of T-ALL treatment and prognosis in children,and also reviews the characteristics of T-ALL immunology, molecular biology and cytogenetics.