Since 1979 Iranian people have been experiencing variety of events that undoubtedly had considerable impact on their Mental Health Status.Islamic Revolution,Iran-Iraq war,recent conflicts with international organizations over nuclear issues are among these events.In this thesis four aspects of Iranian Mental Health have been investigated .Mental health status of adolescents in Tehran was studied .Significant proportion of them were at risk of possible mental disorders.Different methods of poisoning used by parasuicide cases in Tehran between 2000-2004 was investigated.Drugs,pesticides and other agricultural chemicals were the most common methods used.The psychometric characteristics of attitude toward suicide instrument and its feasibility for use in Iran was performed.It should be modified according to Iranian culture.A cross cultural study to analyse similarity of factorial structure of Temperament and Character Inventory was performed on equal sample of Germans,Swedes and Iranian revealed that structure of personality is equivalent across cultures.Modification of considerable number of items in Iranian versions should be done.