The main purpose of this research is to examine empirically the relationship between anxiety and religiosity in individuals in adulthood in terms of religious psychology. Therefore, in this study, it is aimed to explain what kind of relationship there is if there is a relationship between anxiety of death and religiosity in adulthood. The universe of our research constitutes adult individuals living in the city center of Istanbul. The sample consisted of 500 adults living in Istanbul, selected by random sampling. The data acquired as a result of the study were analyzed via SSPS 18.0 package software and arithmetic mean, frequency distribution, pearson correlation and t-test were applied. As a result of our study, it was determined that there is a positive relationship between the anxiety of death and the behavior, emotion and cognition dimensions of religiosity and genereal religiosity. That is, as a result of the analyzes made, it was found that as the anxiety level of death increased in adulthood, the level of general religiosity and the behavior, emotion and cognition dimensions of religiosity increased. On the other hand, no relation was found between death anxiety and religious dimension.