Background: Acute Lymphoblastic Leukemia is the most common cancers in children, originates in the bone marrow and is released into the blood stream. ALL risk factors are numerous; they include genetic, chemical exposure, infection, age, ethinicty and diet. Despite that, there are many studies about the association between diet and ALL incidence, but according to the researcher knowledge, there is no study evaluated dietary behavior, dietary intake and glutamine intake in reduce chemotherapy side effects in ALL patients in Gaza Strip. Aim: To assess the nutritional status of children's with ALL and health determinants among patients attending Abdel Aziz Al-Rantisi Hospital and effect of glutamine intake chemotherapy side effects decrease. Methods: A case-control study design included 80 participants aged 0-6 years; 40 ALL patients and 40 controls. They were selected from Abdel Aziz Al-Rantisi Hospital in Gaza Strip. They were matched by age, sex and region. All participants were interviewed and they filled out questionnaire sheet. Dietary intake was assessed by using food frequency questionnaire. In addition, weight and height were measured for all participants. Moreover, blood samples were collected to measure hs- CRP in serum and another blood tests. Pilot study was conducted for 10 participants (five cases and five controls) and they were excluded. Response rate was 100 %. Results: The mean age of participants was (3 years), among them, 54% were males and 46% were females. This study reported that there was a significant positive association between ALL and the following variables: Consanguinity (P<0.001), Poverty (P<0.001), In vitro fertilization (P<0.001), medical problems of mothers, and family history of ALL. Moreover, it reported that there was a significant inverse association between ALL and Child exposure to sun (P<0.001), breasting (P<0.001) Folic acid intake pre-conception (P<0.001)and healthy diet. There was no statistically significant difference found between case group and control group regarding consumption of meat, legumes and folic acid during pregnancy. Conclusion: There are many modifiable risk factors could contribute to ALL incidence. They include family history of ALL, history of cancer, smoking behavior, physical activity, dietary behavior, dietary intake, serum hs-CRP levels and glutamine protein intake and its relation with decrease chemotherapy side effects. Recommendations: To raise awareness among general population about ALL risk factors and fight against certain risk factors by maintaining healthy body weight, physical activities and making dietary modification to reduce ALL incidence.