Background:: Being affected by cancer may change the self-esteem of children, therefore spiritual care as a prominent factor that affect physical and mental health is effective in their adaptation to the diseases.

Aim: To investigate the effect of spiritual care based on sound heart on the self-esteem of children with cancer.

Method: This is an interventional study that was conducted in 2017 on 40 children attending Dr. Sheikh Children's Educational and Medical Center in Mashhad. Sampling was done by simple random method in the intervention and control groups. The intervention group received a training program based on spiritual care focused on the religion of Islam in 5 sessions over four weeks. Data were collected by demographic questionnaire and "Cooper Smith’s Self-Esteem Scale", and entered into SPSS/20 software. Independent t-tests, paired t-test and covariance test at the significant level of p <0.05 were used to analyze the data.

Results: The independent t-test did not show a significant difference in the self-esteem of children before and after the intervention in the control group, but in the intervention group, it showed a significant difference in all dimensions of self-esteem (p<0.01).

Conclusion: The results of this study showed that spiritual care increased children's self-esteem. Therefore, subsequent studies are suggested with long-term follow-up to help understand the long-term effects of this type of care on ill children.

Keywords: Spiritual care, Sound heart, Self-esteem, Cancer