This article investigates the issue of proving the criminal offenses event in criminal proceedings of illegal gambling in the unity of criminalistics and criminal proceedings. Established that the elements of the criminal offense event in these categories proceedings are a method and form of gambling, and the time and place of its commission. The authors also identified a range of issues which should be answered by the investigator during the investigation and that will allow to establish a criminal offense event. It also provides key recommendations for the investigator to answer all the questions and establish the criminal offense event.

Keywords: gambling, pre-trial investigations, criminalistics providing, event of criminal offense.