The pathophysiology of depression and anxiety implies a mild stressor environment that, act negatively on health and mind of human being and in chronic spectrum initiates deadly secondary pathology. Alteration in the level of three neurotransmitters holds the crucial background of molecular aspects of depression and anxiety. Several external and internal influences have also been reported as major determinants for the occurrence of depression and anxiety, which are severe mental and physical stress, medical condition, and genetic influences. It is very crucial to identify the exact reasons that cause depression and anxiety, because the symptoms of the same will differ person to person. Research suggests that continuous difficulties such as long-term unemployment, living in uncared relationship, loneliness for prolonged period, prolonged work stress are the major reasons to cause depression. Of late combination of events can trigger depression.