Purpose: This study aimed to investigate a clinical effect of Coo-Sun activity focusing on improvement of quality of life in female cancer patients. Methods: The subject of study consisted of 5 female cancer patients at the East-West Cancer Center of OO Oriental hospital. The survey methods of this study are Functional Assessment of Cancer Therapy-General (FACT-G) and State-Trait Anxiety Inventory (STAI). Patients performed Coo-Sun activity 6 times a week and filled out FACT-G and STAI questionnaire after every 3 times training. Results: In FACT-G questionnaire, physical well-being and emotional wellbeing was improved significantly after Coo-Sun activity. And change of social/family well-being and functional well-being score were not significant statistically. In STAI questionnaire, STAI1 was improved significantly after Coo-Sun activity. And change of STAI2 score was not significant statistically. Conclusion: After Coo-Sun activity, quality of life (QOL) in female cancer patients was improved and anxiety was decreased. But this study have limitation to prove effects of Coo-Sun activity completely in female cancer patients. So well designed prospective cohort study will be needed to prove its benefits.