The article is devoted to the theoretical substantiation and conceptualization of the regulatory influence of the state on the development of Ukraine's recreational sector within the paradigm of sustainable development under martial law and wartime economic restructuring. The relevance of the study is determined by profound spatial, institutional, and socio-economic transformations experienced by the recreational sector as a result of armed aggression, as well as by the growing role of public policy in ensuring its adaptability, resilience, and security governance. The purpose of the article is to provide a theoretical justification and conceptualization of the state's regulatory influence on the development of the recreational sector of Ukraine within the sustainability paradigm under conditions of martial law and wartime economic restructuring, taking into account spatial, institutional, and socio-economic transformations. To achieve this purpose, the article analyzes theoretical approaches to state regulation of the recreational sector and concepts of sustainable development in the context of crisis and wartime conditions; examines the impact of martial law on the functioning of Ukraine's recreational sector, in particular the transformation of its territorial structure and resource potential; and determines the role of state policy in ensuring the adaptability and resilience of the recreational sector during wartime restructuring and post-war recovery. The methodological framework of the study is based on a combination of general scientific, special, and interdisciplinary research methods. Methods of analysis and synthesis were used to systematize scientific approaches to state regulation of the recreational sector and sustainable development; a systems approach was applied to consider the recreational sector as a complex socio-economic system interacting with the natural environment and institutional structures; comparative analysis was employed to compare the functioning of the recreational sector in the pre-war and wartime periods; methods of scientific abstraction and generalization were used to formulate conceptual conclusions; and a territorial-geographical approach was applied to assess the influence of spatial factors on the development of recreational activities. The results of the study indicate that under martial law the recreational sector of Ukraine is transforming from a model of mass leisure toward an adaptive, socially oriented, and resilient model. It is demonstrated that the effectiveness of state regulation in crisis and wartime conditions is determined by the ability to combine legal, economic, strategic, managerial, environmental, and resilience-oriented instruments within an integrated regulatory framework. The study substantiates that state policy in the recreational sector during wartime restructuring and post-war recovery should perform a system-forming function, ensuring a balance between security priorities, preservation of natural resource potential, and stimulation of economic activity at the territorial level. The practical significance of the research lies in the possibility of using its results in the development and adjustment of state and regional policies for the development of Ukraine's recreational sector under prolonged security challenges and in the context of post-war reconstruction.