Background: There is an increasing focus among cancer patients on the use of cannabis-based medicine (CBM) as a supplement to conventional palliative care. However, physicians are reluctant to engage in dialog with the patients as clinical evidence is lacking. As a result, the patients are often left alone to rely on their own judgment in purchasing CBM products on the illegal market. Objective: Our study aimed to collect information from CBM treatment-experienced cancer patients receiving palliative care regarding treatment decision rationale and outcome. Design: A qualitative interview study using thematic analysis was performed. Setting/Participants: A total of 20 informants took part in individual interviews. Results: To the question addressing the main rationale for starting CBM treatment, all 20 patients responded that they carried a hope that cannabis would have a curative effect on the cancer disease. Most patients reported relief of symptoms, such as insomnia, anxiety, nausea, and pain, after initiation of CBM treatment, but this outcome was perceived as less of a focus in comparison to hope of a cure. Conclusion: This study contributes with knowledge from the perspective of the cancer patient in palliative care regarding the decision behind the use of CBM. There seems to be striving for surviving cancer based on the rationale that cannabis may constitute curative properties. Relief of symptoms is perceived as a secondary reason for treatment. This knowledge is essential in the dialog between the health professional and the cancer patient about the use of CBM products for treatment.