All social, political and economical progress that was made in the end of 19th century and beginning оf 20th century had a really strong consecuensed a wide reforms of processes of criminal law and criminal proceedings law by a legislation of Republic of Serbia, which showed uneficcience, inert and uneffective plan of crime prevention in practice. Practical analysis proved that it's necessary to make structural changes to pervious criminal procedure, first through the changed act of a public prosecutor, than in aplyying a simplified form of actions in his criminal cases. Effective fight against criminal, which has showing a constant trend of growth, always requiered quick, adequate and contemporary procedure and trial in short time. That was the interest of a whole society, and a defendant too. In that circumstances, principle of opportunity hac become a important instrument that requieres eficient procedure of minor crimes. Ratio legis and criminal political justification of the introduction of this principle in the criminal law of Republic of Serbia, reflected first throuht relief of courts, reduction of the number of cases and rationalization of criminal law. In this way, Republic of Serbia was followed aplyed trends of European comparative legislation, creating conditions for a new aproach of a criminal procedure in threating perpetrators of a minor crimes. The point was in a efficient, effective, and deformalised crime procedures.