Depression is a mood disorder that affects a person’s thoughts, behaviors, feelings, and life at large. People diagnosed with depression experience cluster of symptoms ranging from sad mood, dysphoria, suicidal ideation, hopelessness, helplessness and low self-esteem and often exhibit pessimistic explanatory style. Depression is considered the major cause of disability worldwide and is known as a psychiatric cold. According to World Health Organisation, 350 million people that are approximately 5 percent of the world population are suffering from depression. Women are more often diagnosed with depression than men. The aim of the present paper is to present a general overview cognitive behavior therapy (CBT) in treating depression and the results that this therapy has gained during the past decade. Research studies carried out during the last decades have consistently shown that CBT is efficacious in treating adolescent mental disorders such as depression, anxiety. CBT is based on the interrelations of thoughts, actions, and feelings and in order to work with people under therapy, the aim of therapy remains to identify the pattern of thoughts and feelings that underline the mood and restructuring these thoughts.