The article examines the ecological and legal component of criminal offenses under martial law, since the risk of man-caused accidents and ecological disasters, which threaten security, including environmental and human ones, as well as international legal order, is increasing owing to aggressor-country army’s deliberate actions. It has been argued that the consequences of the military conflict for the environment, human life and health are already considered catastrophic. It has been proven that the ecological crisis should be recognized as an existential threat to the national security of Ukraine. Pressing issues of forming interdisciplinary (synergistic) connections between environmental and criminal law science and other areas of scientific knowledge have been covered. Considering the outlined problem is becoming of a significant relevance due to the fact that certain criminal offenses cause damage to the environment, thus, leading to its destruction. It is a matter of such criminal offence compositions as laws of the war violation (Article 438 of the Criminal Code of Ukraine (CCU) and ecocide (Article 441 of the CCU)). The expediency of improving the current criminal legislation and legal liability mechanism, which would satisfy the proportionality requirement, namely commensurate punishment of severity and consequences of the committed acts, has been substantiated. The expediency of further criminal law prohibition of ecocide in the new CCU Draft has been motivated, taking into account the degree of social danger as well as the severity of large-scale and long-term consequences for the environment and the entire humanity. It has been proven that the state’s environmental function to ensure environmental security, fundamental constitutional environmental rights of citizens, as well as to maintain ecological balance and sustainable development on Ukraine’s territory should become today’s narrative, with the environmental security component to be further included into the sectoral state restoration programs in order to form a new environmental law under martial law both for Ukraine and European countries. Based on our own conclusions and generalizations, proposals and recommendations for improving the current national legislation and greening the sectoral national policy components have been provided. It has been argued that legal mechanisms for fixing and determining the amount of environmental damage caused to natural resources and complexes as a result of armed aggression and hostilities under martial law should be established at the legislative level. environmental safety, environmental damage, environmental damage, environmental right protection, country’s natural resource potential restoration, severity of consequences, state’s environmental function, environmental and legal conflictology