Introduction: The presented article considers the actual problems of countering the ideology of extremism and terrorism in the educational environment. The author analyses the views of authors concerning this problem. The state and dynamics of extremist and terrorist offences are studied. Separately considered criminal acts related to the spread of extremism and terrorism ideology. The criminological portrait of the criminal personality is considered, the causal complex of committing these criminal acts is indicated, the directions of their prevention and prevention are considered. Methods and Materials: The normative-legal base of the study was formed by the Constitution of the Russian Federation, federal laws regulating the issues of countering extremism and terrorism, as well as scientific works that explore this issue. The methodological basis of the work was the general dialectical method of scientific cognition. Also methods of logical deduction and induction were used. Along with this, cognitive methods and techniques of observation, comparison, analysis, generalisation and description were used. The Results of the Study: made it possible to consider and analyse the problematic issues of the spread of extremist and terrorist ideology committed in the educational environment, as well as to propose certain countermeasures. Findings and Conclusions: An in-depth study of all aspects of the spread of extremist and terrorist ideology in the educational environment will contribute to the development of effective and timely preventive measures in this area.