The risk of metabolic late effects after childhood cancer, such as obesity, hypertension, and diabetes, can be positively influenced by a healthy lifestyle with sufficient physical activity. Nevertheless, studies on physical activity in adult survivors of childhood cancer are scarce and involve different and often nonvalidated questionnaires. We used the Short QUestionnaire to ASsess Health-enhancing physical activity (SQUASH), which was developed and validated to assess daily life physical activity in the Dutch adult population. The aim of the study was to assess daily life physical activity in Dutch adult long-term nephroblastoma and neuroblastoma survivors. Sixty-seven nephroblastoma and 36 neuroblastoma survivors (median age, 30 y; range, 18 to 51 y) and 60 sociodemographically similar healthy control subjects (median age, 32 y; range, 18 to 62 y) were asked to complete the SQUASH during their regular follow-up visit. The adjusted mean physical activity score in male neuroblastoma survivors (mean, 7155; P=0.004) was significantly lower than in male controls (mean, 10,574), whereas it was not significantly lower in male nephroblastoma survivors (mean, 9122; P=0.108). Adjusted means for physical activity scores in females were not different from their controls. In conclusions, male neuroblastoma survivors were identified as performing less daily physical activity.