Smokers have a higher incidence and prevalence of mental illness than the general population. Smoking cessation treatment in this group of patients is diffi cult. This study aims to provide a review of the association between smoking and psychiatric disorders. Method: A selective review of the relevant clinical literature was conducted. The authors present a review of articles about smoking and depression, panic disorder, schizophrenia, attentiondefi cit hyperactivity disorder (ADHD), Alzheimer´s disease and substance abuse. Results: Psychiatric comorbidity is common in smokers, especially depression, schizophrenia, ADHD and drug abuse. Smoking is associated with greater risk of panic attacks, and cohort studies are necessary to investigate the possibility of an inverse relationship between nicotine intake and incidence of Alzheimer´s disease. Conclusion: There is increasing evidence of high rates of psychiatric comorbidity in smokers. Further studies of the association between smoking and psychiatric comorbidity are necessary to understand this complex relationship.