Acute lymphoblastic leukemia (ALL) survivors were screened for risk factors of cardiovascular disease. Forty-four ALL survivors in first remission were enrolled. Twenty-six also received 12-18 Gy cranial radiotherapy (RT). Patients' body mass indexes (BMIs) at dignosis and during the study were compared. Metabolic syndrome (MS) evaluation was performed in patients, parents, and siblings older than 6 years. Homeostasis Model Assessment (HOMA) index of the survivors was also calculated. In survivors with impaired fasting glucose levels, oral glucose tolerance test (OGTT) was performed. Thyroid functions and IGF-1 and/or IGFBP-3 levels of the survivors who received cranial RT were evaluated. Median age of the survivors was 11.5 years (6-23). At diagnosis, mean BMI percentile was 46.7 (3-95) andmean z-score was-0.09 +/- 1.14; during the study, these values rose to 71.1 +/- 25.6 (3-100) and 0.8 +/- 0.94, respectively (P < .001). One patient (2.2%) and nine survivors (20%) were obese at diagnosis and during the study, respectively (P = .005). Survivors had significantly higher BMI percentile and BMI z-score compared to their siblings (P = .006 and P = .011, respectively). The study group was small and we could not show a correlation of the patients' obesity with RT, thyroid functions, IGF-1, and IGFBP-3 levels. In three survivors (6.8%), there was MS. Maternal and paternal MS was not found as a risk factor for MS of the survivors (P = .1, P = .5, respectively). The HOMA index revealed insulin resistance (IR) in 12 (27.2%) of the survivors, whereas OGTT revealed abnormal glucose regulation and/or IR in four. As a conclusion, ALL survivors have high risk for obesity and MS.