Studies in mental health is to increase the positive emotions of the person and to reduce the negative emotions, beliefs and thoughts. Especially after positive psychology, many studies have been carried out to ensure that individuals have positive emotions. However, in recent studies, it has been determined that individuals avoid not only negative emotions but also positive emotions. Thus, you suppress your positive emotions because of fear of happiness. The individual's beliefs and cultural values also affect mental health. The person is afraid of being happy because of these beliefs and cultural values. Fear of happiness is the avoidance of happines. When people believe thet unhappiness will come immediately after happiness or that the environment will be harmed after being happy, fear of happiness occurs. Fear of happiness harms both the mental health and social relations. Morever, fear of happiness is associated with alexithymia, anxiety, stress, fear of compassion, antisocial, cognitive distortions related to relationships, panic disorder and especially depression. It is extremely important to know and define the fear of happiness for an effective treatment interventions. Fear of happiness rests in maladaptive schemas in early life, not meeting their needs warmly and sincerely in childhood, punishing them when they experience positive emotions, and growing up in a family with unhealthy family patterns. In this study, it is aimed to define fear of happiness, to determine the protective and risk factors, to determine the causative factors, to explain the related concepts, and so to raise awareness about fear of happiness.