Circadian typology (morning-type, neither-type, and evening-type) is an individual difference which has been related to numerous aspects of mental health. In this paper we present a review of the findings published on this topic. After searching in-the main databases a total number of 70 works were selected, published in. Spanish and English from 1990 to 2012 collected in the databases ISI Scopus and Medline. These works show that individuals with evening-type typology exhibit a greater prevalence of seasonal affective disorder, mayor depression, bipolar disorder, schizophrenia, eating disorders, sleep disorders, addictive behaviours, ADHD, and higher anxiety levels than morning-type typology individuals. In this sense, the evening-type is considered as a factor of risk whereas the morning-type would be a protective factor for the development of several mental disorders. This could be a result of clock gene polymorphisms, social jet lag and some personality traits. Circadian typology must be considered in the evaluation, treatment and prevention of the mental disorders, as it affects to the start, course, remission and relapse of diverse problems of mental health. Chronobiological therapy must be also considered in the therapeutic approaching when the circadian rhythmical expression is altered.