Background/aim: The aim of this study was the determination and prospective follow-up of quality of life, depression, and anxiety in pediatric patients with cancer under chemotherapy, as well as the evaluation of related factors. Materials and methods: Fifty newly diagnosed pediatric cancer patients and their parents were prospectively monitored before, during, and after therapy, and tests were used. Results: Significantly lower quality of life scores were recorded during treatment, in the group with CNS tumors, in the group receiving chemotherapy plus radiotherapy plus surgery, in the inpatient-only treatment group, in the group receiving treatment for longer than 6 months, and in the group of patients whose diagnosis was delayed for more than 3 months. Total quality of life scores for children and their parents were 82.95 ± 14.59 vs. 83.61 ± 14.60 before, 54.69 ± 16.51 vs. 55.78 ± 16.05 during, and 83.88 ± 12.44 vs. 84.19 ± 13.22 at the end of treatment (P < 0.05). Anxiety and depression scores were significantly higher during treatment, in patients whose diagnoses were delayed for more than 3 months, and among inpatients. Conclusion: The quality of life of a majority of our patients was severely affected, and depression and anxiety were more frequently seen especially during treatment.