The article considers the mechanism of transport crime basing on the polyergatic essence of rail, water and air transport and on monoergatic essence, i.e. vehicles. It gives the classification of ergatic systems, their relationship, analyzes the disputable issues of crime mechanism in general and negligent crimes in particular, formulates the concept of transport crime mechanism, stands its objective (technical system, informational system and situation) and subjective (subject to drive the transport) elements, shows the distinction between criminal and criminological concept of crime mechanism, the ways of harming public relations characterizing safety of transport operation