Religiosity is a comprehensive and complex term encompassing institutionalized religious attitudes, beliefs and activities. In patients with schizophrenia, religiosity is more prevalent than in the general population, and has significant associations with the course of illness and treatment outcomes. Nevertheless, its significance is still underestimated in clinical practice. The majority of studies on religiosity in schizophrenia patients are of the cross-sectional type, so it is difficult to reach conclusions about cause-and-effect relationships. Evidence to date suggests an association of intensity and various dimensions of religiosity with different clinical presentation, adherence, and comorbidities. Higher rates of religious delusions were reported, as well as lower rates of adherence, substance abuse and suicidal ideation. The mere presence of religiosity seems to be more important than belonging to any specific religion, although it has been proven that patients of different religious denominations differ in both prevalence and type of religious delusions. One of the most important elements of religiosity is religious coping. Positive religious coping is associated with a more favorable clinical presentation and higher quality of life, while negative religious coping is associated with a significantly worse course and outcome of illness. Although modest, data on the attitude of health care providers towards their patients indicate insufficient knowledge of their religiosity, but also of religiosity in general. It is possible that the integration of the religiosity and spirituality of each individual patient into the therapeutic process leads to more favorable outcomes in the treatment of schizophrenia.