Long-term results in the treatment of 116 patients of acute lymphocitic leukemia with ages between six months and seven years are reported. A first group A, formed by 76 patients, was treated with prednisone and vincristine as induction protocol and maintenance therapy with 6-mercaptopurine or methotrexate. No neuromeningeal prophylaxis was made, except some cases in which intratecal methotrexate was applied. 27 patients are alive, 21 of them (27,6%) remain in complete remission for more than three years. A second group B, formed by 40 patients, was treated more recently; with an induction protocol composed by prednisone, vincristine and L-asparaginase. All patients in this group received cranial irradiation and intratecal methotrexate. 31 patients are alive (77,5%), 13 of them (32,5%) remain in complete remission for more than two years. The evolution period in this group B is shorter, but some features are exposed which suggest the possibility of long-term better results.