Background: is study aims at investigating the effect of music therapy and painting therapy on pain severity, sleep quality and behavioral disorders of children with cancer. Method: The research method is experimental and quasi-experimental with two experimental groups A and B and control group and was performed in two time periods of pre-test and post-test. The statistical population consisted of all children aged 5-12 years suffered from cancer and the sample included 30 children with cancer in Omid Hospital in Isfahan selected by convenience sampling method and were randomly separated in three groups. Data collection tools in this study included Wong-Baker faces pain rating scale, Owens children's sleep habit questionnaire (2000) and Quay and Peterson’s revised Behavior Problem Checklist (RBPC). The data obtained from the questionnaires were analyzed in two pre-test and post-test intervals using SPSS-24 software. The results of Wilcoxon test showed that art therapy by two methods of music therapy and painting therapy has a negative effect on pain severity in children with cancer. Results: The results of the paired sample t-test showed that art therapy by two methods of painting therapy and music therapy is effective on sleep quality of children with cancer. The results of the paired sample t-test showed that art therapy by two methods of music therapy and painting therapy is effective on behavioral disorders in children with cancer. Conclusion: As a result, since the complications of diagnosis and invasive drug treatments for children with cancer are very stressful, applying non-pharmacological approaches appropriate to the capacity of children, including music therapy and art therapy are useful in reducing their physical and psychological problems.