Abstract: Among many indigenous peoples of Amazonia, shamanism and Christianity co-exist as central cultural elements shaping the ways in which people interpret and interact with the world. Despite centuries of co-existence, the relationship between shamanism and Christianity has entered an especially dynamic era as many of Amazonia’s indigenous peoples abandon Catholicism for Evangelical and Sabbatarian churches. Testing the relationship between Christian church affiliation and shamanism in 23 Makushi and Wapishana communities in southern Guyana, we found that Evangelicals and Sabbatarians are less likely to visit shamans or accept their legitimacy than are Anglicans and Catholics. However, conversion does not necessarily imply a complete rejection of indigenous religious systems as many self-identified Evangelicals and Sabbatarians continue to adhere to some indigenous beliefs and practices. We conclude by positing possible implications of religious conversion for natural resource use on indigenous lands.