Introduction: Cancer leads to several psychological consequences such as anxiety and depression, and interventions based on finding meaning in life can help reduce these complications. This study aimed to investigate the effectiveness of logotherapy based on Rumi's thoughts in death anxiety and depression among women with breast cancer. Materials and Methods: This was a quasi-experimental study with pre-test, post-test, and a control group. The statistical population of the study included all women with breast cancer admitted to the psychosomatic center of Imam Khomeini Hospital in Sari in 2021. Thirty patients were selected by purposive sampling method and randomly assigned to experimental and control groups (15 patients in each group). For the experimental group, a logotherapy based on Rumi's thoughts was performed in 8 sessions of 75 minutes, and for the control group, no treatment was performed. Death anxiety scale and Beck Depression Inventory were completed by participants in the pre-test and post-test stages. Analysis of covariance was used to analyze the data. Results: According to the results, in the experimental group, the death anxiety and depression scores were 12. 93±, 3. 83 and 52. 29±, 12. 47 in the pre-test, which were reduced to 8. 16±, 2. 31 and 43. 08±, 10. 23, respectively, in the post-test. In the control group, the death anxiety score in the pretest was 13. 22±, 4. 15 and the depression score was 50. 97±, 11. 46, and in the post-test, without significant changes, they were 12. 78±, 3. 89 and 49. 88±, 9. 34, respectively. Therefore, logotherapy based on Rumi's thoughts significantly reduced the scores of death anxiety and depression in women with breast cancer (p<0. 001) in the experimental group, while in the control group, no such change was observed (p>0. 001). Conclusion: Based on the results of this study, it seems that logotherapy based on Rumi's thoughts can be effective in improving the level of death anxiety and depression in women with breast cancer.