The content of social relations in the sphere of use and protection of natural resources as an object of legal regulation is researched. It is proved that relations regarding use and  protection of environment at whole and its natural complexes in particular have to be regulated by ecological law, but relations regarding use and protection of separate natural resources such as land, forests, water, mines and so on are to be regulated by resourced branches of law, correspondingly by land law, forest law, water law, mine law etc. The conclusion that ecological law as well as land law, forest law, water law, mine law etc. are separate and independent branches of legal system of Ukraine is formulated. Also it is concluded that codification of ecological law should not go out of limits of the object of its legal regulation. Finally, structure of the system of land law of Ukraine is defined.