The influence of the media on public opinion and shaping it has expanded significantly in the last decade with the formation of social media and availability of these media at any time and place. If in the past, the media was under the control of the ruling system on one side and the opposition on the other side, and there were not many neutral media, currently. This situation has changed and every person can be a media whit his smart phone and create a news channel in virtual space and then attract more audience in competition with other channels and increase the influence of his news analysis on public opinion. It is easy to see how the mass media are able to create a kind of like-mindedness, pain and similarity between the people of a country and even the world. The media can be a source that shows the facts to the people and by reflecting and distorting the news and analyzing the events, it tries to influence the public opinion. Criminal issues and excesses in the unregulated publication of the details of the issue and creating sensitivity in the public opinion of the proceedings have gone out the normal process, and in many cases, haste and haste in the proceedings and issuance of severe sentences and the speed in their implementation have caused justice to be sacrificed and finally, it will end in criminal populism. This article tries to explain the characteristics and nature of the media and its role in the formation of thoughts in an analytical and descriptive way public and its effects on criminal justice in the media subjects.