Overweight and obesity in the pediatric population remains a growing worldwide health burden. The extent to which this trend extends to childhood cancer survivors (CCS) remains less well explored. We conducted a retrospective observational study from a single institution in Saudi Arabia to estimate the prevalence of overweight and obese status among CCS over a five-year period. A total of 91 CCS patients were identified, 63 of whom had complete weight data from their treatment to the time of the study. Of these patients, 29 (46.0%) were found to be overweight or obese [body mass index (BMI) ≥85th percentile] at the time of the study. Of these patients, this rate was particularly high for patients who were female, older at the time of diagnosis (>6 years) (72.8%) and among pubescent patients (Tanner 3-5 at diagnosis). The rate of overweight and obesity increased from 31.7% immediately after the end of treatment (average age of 7.1 years) to 36.5% one year after. Thereafter, these percentages increased to approximately 38% over the 5-year follow-up period and increased beyond that up to 46%. A high prevalence of overweight and obesity among CCS was found at the end of their treatment with an observed increasing trend towards overweight and obesity in the following years, suggesting the need for early and continuous intensive intervention and frequent dietary evaluation.