Purpose: Investigations into the role of spirituality in cancer confirm the association of good spiritual well-being with many positive outcomes. This study aimed to evaluate potential changes in spirituality over the course of radiation therapy (RT). Patients and Materials: The Functional Assessment of Chronic Illness Therapy–Spiritual questionnaire measuring spiritual well-being and quality of life (QOL) was administered to adult patients undergoing RT. Scores were compared using student t tests and chi-square analysis. Results: Despite statistically significant declines in QOL measures such as physical well-being (P < .001) and overall well-being (P < .001), no significant changes were noted in spirituality for all comers. A significant increase in the Sp-12 spirituality measure (P = .001) was noted in patients with breast cancer, independent of age, gender, and purpose of treatment. Sp-12 scores were positively correlated with overall QOL scores (P < .001).