Purpose: The purpose of this study was to understand the meaning of prayer in Christian patients with breast cancer. Methods: Data collection and analysis were conducted by the Colaizzi analysis of phenomenological method. Data were collected by in-depth interviewing the participants and by further follow-up observations. Sixteen patients participated in this study. Results: The significant statements (188), formulated meanings (42), themes (38), clusters of theme (10), and categories (5) were emerged. The 5 categories were as follows: communication with God, healing and peace, spiritual growth, distrust in prayer, and method of prayer. Conclusion: Further studies need to consider the period of faith, comparison between christian and other religions, and length of diagnosis. A better understanding of the meaning of prayer will lead to a more comprehensive view of the spiritual care for patients with breast cancer, and can lead to guidelines for assessment and intervention to reduce suffering from cancer.