Abstract: Objective: To investigate the changes of nutritional status in pediatric Acute Lymphoblastic Leukemia (ALL) patients during therapies for remission induction with L-asparaginase (L-asp). Methods: Prospectively collected a total of 49 pediatric patients diagnosed with ALL and undergoing therapies for remission induction with L-asparaginase in Shanghai Children's Medical Center from July 2014 to April 2015. Recording laboratory index and anthropometric measurements once a week during the period of using L-asp. Measuring the body composition on the day before using L-asp and on the final day of using L-asp. The gender, age, the risk of the disease, and if using human serum albumin were also recorded. Results: During the therapies for remission induction with L-asp in pediatric ALL patients, the mid-upper arm circumference decreased significantly(P<0.01) and the triceps skinfold increased significantly (P<0.01). The differences were statistically significant. Meanwhile, the fatfree body weight and the muscle mass decreased significantly (P<0.01). The serum albumin decreased significantly (P<0.01). The differences were statistically significant. Conclusions: These pediatric ALL patients had different degrees of hypoproteinemia and had fat-free mass loss during the therapies for remission induction with L-asp. They need nutrition support at the beginning of the therapy to get a better nutritional status.