In this thesis How religiosity affects anxiety and depression among young people, we look at the relationship between three complex concepts; religiosity, anxiety and depression. Starting from the assumption that religiosity has a good effect on the mental health of young people, we saw that we are faced with a challenging and difficult to measure influence of religiosity on young people, and then an even more complex measurable relationship of the influence of religiosity on anxiety and depression in young people. However, religiosity in certain ways and mechanisms affects a young man who, in his youth, finds himself in a very turbulent and extremely stressful period, full of drastic and sudden changes. Through three chapters, as the work is structured, the goal was to show whether religiosity acts as a protective or risk factor in preserving the mental health of young people. It is very important to define what religiosity, anxiety and depression are in order to better understand their relationship. As the religiosity of a young man is influenced by many factors; parents, peers, school, religious institutions, mass media, etc. we presented in the second chapter. Where we looked at the role of religiosity on the mental health of young people; highlighting some positive and negative or risky sides of its activity. In order to confirm all of the above, in the last chapter we analyzed several studies and their results on this topic. Through several studies, we were able to see whether religiosity is a positive or negative factor on symptoms of anxiety and depression.