Аннотация:Abstract: the article is devoted to the analysis of the legal nature of the requirements of good faith, reasonableness and fairness provided for in paragraph 2 of article 6 of the Civil Code of the Russian Federation to overcome gaps in law. The necessity of considering these requirements from metatheoretical methodological positions that allow covering various aspects of their essence is established. The requirements of good faith, reasonableness and fairness manifest themselves in civil law as: spiritual and moral foundations, principles, presumptions, legal norms, legal obligations, the criterion for interpreting legal norms. The variety of semantic shades and functions of these requirements, as well as their close connection with morality, their elementary nature and obviousness, allow us to qualify them as civil law axioms.