The present paper systematically reviews studies examining the potential beneficial or harmful effects of religious/spiritual coping with cancer. Using religion and spirituality as resources in coping may be specifically prevalent in patients with cancer considering the potentially life-threatening nature of the illness. Religious/spiritual coping may also serve multiple functions in long-term adjustment to cancer such as maintaining self-esteem, providing a sense of meaning and purpose, giving emotional comfort and providing a sense of hope. Seventeen papers met the inclusion criteria of which seven found some evidence for the beneficial effect of religious coping, but one of these also found religious coping to be detrimental in a sub-sample of their population. A further three studies found religious coping to be harmful and seven found non-significant results. However, many studies suffered from serious methodological problems, especially in the manner in which religious coping was conceptualised and measured. The studies also failed to control for possible influential variables such as stage of illness and perceived social support. Due to this, any firm conclusions about the possible beneficial or harmful effects of religious coping with cancer is lacking. These problems are discussed and suggestions for future studies are made.