Aim of our study was to evaluate the influence that shift work and night work could have on mental health. A review of literary articles from 1990 to 2011 on shift work and night work was carried out. The results of this review confirmed that the shift work and night work affect mental health with the onset of neuropsychological disorders such as mood disorders, anxiety, nervousness, depressive anxiety syndromes, chronic fatigue and chronic insomnia irritability, sleep disturbances, reduction in levels of attention, cognitive impairments, alteration of circadian rhythm. Night work and shift work cause severe desynchronization of the cronobiological rhythms and a disruption of social life with negative effects on performance at work, on health and on social relationships. In the light of these results and recognizing shift work and night work as risk factors for the health of workers is necessary to implement preventive and periodic health checks by the occupational doctor to ensure the health and safety of workers taking account of the different environmental and individual factors.