The subject of this paper is to attempt to assess the legal regulation relating to the conservation of the resources, formations and elements of the nature in the agricultural activity carried out in the areas covered by one of the forms of the nature conservation. The analysis of the Nature Conservation Act of 2004 demonstrates that the legislature put in place a few limitations of the agricultural activity, related to the use of resources and elements of nature in the valuable areas due to the natural values. The scope of the prohibitions and restrictions laid down in the specific form of nature conservation depends on its objectives and functions. The subject of the analysis was the legal term “rational agriculture” with respect to the intended sustainable use of the natural resources. In the present Act, one claimed lack of specific instruments introducing requirement or even encouraging the making, in areas covered by conservation area, including agricultural activities, which helps to maintain high nature value. Ordering the terminology and adapting it to modern concepts of environmental protection, regulation of forest management, it would be time to replace the term “rational agriculture” to “sustainable agriculture”, referring to the modern concept of sustainable socio–economic development, the needs of environmental protection. It should be more precisely defined in relation to the term of the existing legal standards for environmental protection in agricultural activities, such as cross–compliance requirements. Regardless of the adopted terminology the legal term rational or sustainable farming should be referenced to the cross compliance requirements.