Abstract: The research object is expert experiment as a method of scientific research and practical cognition, its importance for the formation of the theory of methods of forensic analysis within the general forensics theory and authenticity of expert’s opinion. The article studies the problem of methodological support for expert experiment. The author gives attention to the practicability of the development of expert experiment techniques with account for its specific aims, and considers the stages of expert experiment, and formulates the conclusions about their number. The research methodology is based on materialist dialectics and tre related general methods: formal-logical, comparative-legal, system-structural, statistical methods, generalization of expert practices, etc. The scientific novelty of the research consists in the fact that the present research is considered as a complex research of experiment in judicial expert practice. The aim of the research is to develop theoretical fundamentals which would organize knowledge about this method, and practical recommendations for raising the effectiveness of using its results in the activities of law-enforcement bodies.