Background: Malnutrition (under and overnutrition) occurs in children with solid tumors and has been linked with adverse outcomes during and after treatment. Assessment of nutritional status (NS) can be challenging due to large tumor burdens, atypical growth patterns and different methods for assessing NS. Methods: Retrospective longitudinal study of children with solid tumors (n=61). Anthropometric data assessed [(diagnosis, after diagnosis (1.5, 3, 6 and 12 months, 5 years), end of treatment (EOT), initial cancer survivorship program (CSP) visit]. Registered dietitian nutritionist nutritional assessment (NA) during treatment and Intensity of Treatment Rating (ITR) documented. Results: At diagnosis, prevalence of undernutrition [(Z-score -1.0 to -2.99)] and overnutrition (Z-score ≥ +2.0) were 13.8% and 8.6%, respectively; weight status categories, 8.6%, 6.9%/13.8% were underweight, overweight/obese, respectively. Weight loss and decreased weight-for-age Z-score (WAZ) occurred in 31.9% and 74.5% patients, respectively, at 1.5 months. At EOT, compared to diagnosis, WAZ and height-for-age Z-score (HAZ) decreased and BMIZ increased. From EOT to CSP visit, overweight/obesity doubled, 7.7%/5.8% and 15.2/11.9%, respectively. Thirty-one percent of patients received a NA, occurring at lowest WAZ. Over 50% had ITR of level 3 or 4 and 88.9% had NA in level 4. Conclusions: Suboptimal NS continues at diagnosis, during treatment and survivorship. Normalized measures, accounting for expected growth, should be used instead of raw numbers. More than one nutrition indicator will identify atypical growth patterns and a proactive approach would help prevent malnutrition. Evidence based research is essential and collaboration necessary to meet the needs of this population.