Background. - Internet has become a major tool for patients to search for health-related information and to communicate on health. We currently lack data on how patients with psychiatric disorders access and use Internet to search for information on their mental health. This study aimed to assess, in patients followed for a psychiatric disorder (schizophrenia, bipolar disorder, mood and anxiety disorder, substance-related and addictive disorders and eating disorders), prevalence of Internet access and use, and patient expectations and needs regarding the use of Internet to search for mental-health information depending on the psychiatric disorder. Methods. - We conducted this cross-sectional study between May 2013 and July 2013 in 648 patients receiving psychiatric care in 8 hospitals from the Region Centre, France. We used multivariate logistic regression adjusted for age, gender, socio-educational level and professional status to compare use, expectations and needs regarding Internet-based information about the patient's psychiatric disorder (65-items self-administered questionnaires) as a function of the psychiatric disorders. We identified patients clusters with multiple correspondence analysis and ascending hierarchical classification. Results. - Although 65.6% of our population accessed Internet at home, prevalence for Internet access varied depending on the type of psychiatric disorder and was much more related to limited access to a computer and low income than to a lack of interest in the Internet. Most of the patients who used Internet were interested in having access to reliable Internet-based information on their health (76.8%), and most used Internet to search for Internet based health-information about their psychiatric disorder (58.8%). We found important differences in terms of expectations and needs depending on the patient's psychiatric disorder (e.g., higher interest in Internet-based information among patients with bipolar disorder, substance-related and addictive disorders and eating disorders). We identified three clusters: younger patients with depressive or anxiety disorders and higher Internet access and Internet use; older patients with low socio-economical status and low Internet access and Internet use; patients receiving long-term care for schizophrenia, with low Internet access and Internet use. Conclusion. - Patients with psychiatric disorders reported average use, needs and expectations for Internet-based health information comparable to the overall population. However, Internet use, needs and expectations for Internet-based mental health information differed between patients depending on their psychiatric disorder. Internet-based information and communication for mental health should be designed specifically for each psychiatric disorder. (C) 2017 Elsevier Masson SAS. All rights reserved.