Problematic issues related to the legal basis of the activities of law enforcement agencies under the legal regime of martial law are caused by significant threats to Ukrainian statehood, sovereignty, and territorial integrity of Ukraine. These aspects have become particularly acute after February 24, 2022, as a result of the full-scale invasion of the Russian Federation, which determines the relevance of the topic. The purpose of the study is to determine the legal basis for the activities of law enforcement agencies under the legal regime of martial law in the light of the latest socio-economic, ideological and security issues. Such methods as analysis, synthesis, deduction, induction, logical and legal method and forecasting were used in the article. Within the scope of the study, separate organizational and legal principles were singled out, which most widely illustrate the depth of changes in the activities of law enforcement agencies under martial law. The principle of situational implementation of new services to help the population is reduced to the fact that law enforcement personnel provided services to accommodate the population in shelters, provide drinking water and food to vulnerable groups, etc. The rule here is that for there to be an effective content in countering a separation, there is that need in revealing the prism's that exist which will be able in preventing the measures used in preventing armed group which to a greater extent will continue to be a threat in State's building a stable foreign policies.