The article is focused on the study of the frame structure of the concept of secret based on English-language literary fiction. A concept is a mental representation of knowledge about a certain object, phenomenon, feature, or action. There are different types of knowledge representation structures: mental model, scheme, image, frame, scenario, gestalt. It is the frame that allows us to cognitively represent knowledge about the world. A frame is a structure of information used to represent a stereotypical situation, which is why this study focuses on the frame representation of the analyzed concept. The analysis of the dictionary definitions of the concept of secret has enabled us to identify the following conceptual features: information known to a narrow circle, confidentiality (verbalized by the lexemes — known by few people; shared confidentially with a few; should not be told to others; kept hidden); method for achieving a goal/success (method for doing sth well; the best way of achieving something); something mysterious, incomprehensible/something that is difficult to explain (mystery; cannot be explained/understood; unrevealed). Various aspects of the concept of secret are represented by subject frames (possessing one’s own or someone else’s secret; concealing or disclosing a secret; the existence of a secret in a certain social setting; discussing a secret; a secret as a surprise, or, by contrast, as shameful information), action frames (to report a secret; to hide a secret; to demand to reveal a secret; to promise to keep a secret), as well as by possessive frames (to possess a secret). The analysis of the characters’ speech in English-language novels has been helpful to unveil the following frame units of the concept secret: on the part of the subject: keeping a secret (the need to keep a secret, the protection of a secret by lying) and disclosure of a secret (due to situational necessity, one’s own emotional nature, the desire to show off one’s own knowledge, accidental disclosure of a secret, the use of “secret” knowledge as hints or warnings); on the part of the object: the demand to disclose a secret (asking the interlocutor for a secret and the requirement to avoid secrets) and the promise to keep a secret.