The aim of the study was to estimate growth curve and body mass during and after a treatment of ALL. Retrospective study group included 48 children (27 boys and 21 girls). The age at the start of the treatment varied from 1.4 up 17 years, during our evaluation 4.6-25.4 years. Patients were treated according to modified American (New York Protocol) and German (BFM) protocols. 43 children received central nervous system radiation in a dose of 14-24 Gy. All children completed the treatment protocol and are in the remission. Growth velocity and body mass were estimated during and after the ALL treatment. During the treatment growth retardation was observed at 34 children (2/3 patients). No significant difference in growth velocity was found between group of standard and high risk of ALL. Combined radiotherapy and chemotherapy has probably more influence for growth retardation than chemotherapy alone. Obesity was stated at 13 patients (27%), mostly boys. After the treatment 9 children were permanently obese. Body mass deficiency was found at 5 patients during the treatment and was the same when the treatment protocol was completed.