The term environmental crime is understood as the commission of environmental crimes. The perpetrator focuses on environmental components such as water, soil, air, trees, plants or animals. Environmental crime is currently a global problem and it is very important that we address this issue. Otherwise, incalculable damages on environmental components may occur. The bachelor thesis deals with the issue of environmental crime, which is more and more often a common issue in society. The aim of the work is to present information about criminology and its field – environmental crime and methodology of investigating environmental crime. The first part of the work deals with criminology and its system, characteristics of criminological methodology in general and criminological methodology in investigation of environmental crime as well as the situation in Slovakia. The second part of the work is devoted to case studies – illegal landfill of waste and illegal logging.