Background: Switzerland is a traditional immigration country with immigrants from both neighbouring, and less developed countries. Since the early 1990s, the migration rate has continuously increased and in 2013 almost a quarter of Swiss residents had an immigration background. Immigrants in Switzerland had fewer psychiatric hospitalisations, but more emergency and compulsory admissions than the local population. Therefore it is important to study the characteristics of the immigrant population presenting at the emergency department for mental health problems. Methods: Our retrospective data analysis included adult patients (age ≥ 16 years) admitted to our emergency department who consulted a psychiatrist, between 1st of January 2007 and 30th of October 2012. Results: Clinical data from a total of 1115 patients were available for analysis. Of these, 58.6% (n=654) were male and 41.4% (n=461) female. The mean age was 36.3 years, with a range of 16–85 years. The most common reason for psychiatric presentation to the emergency department was psychosis (n=227, 20.3%), followed by social problems with 18.2 % (n=203), auto-aggression with 16.4% (n=193) and 16.2% (n=181) suffering from depression. Conclusions: Translation services are very important. Therapy adherence programs for psychosis and autoaggression prevention programs are especially important for immigrants.