In this graduate thesis I am concerned with the elaboration of the procedure towards the defendants with mental disorders. First part of the work is devoted to general definition of sanity, regarding insanity which is the result of the mental disorders. Insane person is not guilty and cannot be pronounced with criminal sanction as in the time of realization of legal features regards criminal act as a result of its mental illness, temporary mental disorder or other heavy mental disorder has not been able to comprehend the meaning of its actions and its repercussions . According to such a person is being processed according the law on protection person with mental disorder. Second part of the thesis refers to the procedure itself in accordance with the above and by the Law on general criminal procedure. The procedure for forced accommodation of insane person in a psyhiatric institution is based on solution delivered to the competent regional court, with the transcript of the verdict by which it was established that the accused committed the criminal offense in the insane state, findings and opinions of expert witnesses and other necessary documents.A person with mental disorders and their rights are in a certain way decreased just as they di din most cases they are not capable during the procedure Protect their interests.That's why through procedural laws has been built a mechanism which provides the protection of their rights and interests.When applying these regulations, courts and other state bodies which participate in the procedure must be aware of the special position of such persons, the reasons for which they are entitled but also those that caused them to be denied. To the persons who committed the offense in a state of reduced count and there is a danger from repetition of a criminal offense, the sentence is pronounced the punishment of compulsory psyhiatric treatment which can never be Self-imposed sanction but an addition to prison sentence. In continuation of this thesis i will look at the more detailed elaboration of some legal institutes and procedures regarding perpetrators of criminal offenses under mental disorders.