The aim of the study is to determine how Islamic belief and spiritual well-being affect the attitudes of individuals towards organ donation. The study was designed as a descriptive-relational study and included the participation of 402 adults in the eastern Mediterranean region of Turkey. For data collection, a personal information form, the Organ Donation Attitude Scale, and the Spiritual Well-being Scale were used. A statistically significant relationship was observed between the acceptance of organ donation according to Islamic beliefs and organ donation attitude. A negative relationship was found between organ donation attitude and the scores on the anomie sub-dimension of the Spiritual Well-being Scale, while a positive relationship was found between organ donation attitude and the scores on the transcendence and harmony with nature sub-dimensions. It was concluded from the results that Islamic belief and spiritual well-being have an effect on the organ donation attitudes of individuals.