"Narrative discourse" is a definitive term within the discipline of linguistics in the field of narratology. Narrative discourse is a type of discourse in the category of pragmatics (as opposed to semantics) and has specific defining features. Firstly, as a type of discourse in pragmatics, a speaker and an addressee are both participating in a context of utterance so that the speaker makes expression choices and the addressee makes interpretive choices based on generally observed principles and in accord with the goal of the speaker (not the intention of the addressee).
Secondly, a discourse is defined by lexical and grammatical features that emphasize main material of expression (as opposed to emphasis on supportive material); have a theme to develop; have a recognizable style; and present a main framework within which the addressee interprets knowledge and expectations expressed by the speaker. Narrative discourse is but one kind of discourse; a few others are repartee discourse, compound discourse, and expository discourse.
Thirdly, because of its categorization in pragmatics as one type of discourse, narrative discourse has defining characteristics. These structural characteristics are as follow. A narrative discourse provides an account of events (usually past events), organized chronologically, with one event contingent upon, or happening because of, a preceding event or events. Lexical choices are verbs of action, speech and motion that describe the series of contingent events as told by the speaker from a first or third person point of view. The content and context of narrative discourse is oriented around one or more agents who are the performers of actions.
The well known component parts of a narrative discourse are the exposition or setting; the inciting moment; the developing conflict; the climax; the denouement; the final suspense; and the conclusion, or resolution. Some examples of narrative discourse are historical events, personal events, folk tales, mythology. [Further information is available via the hyperlinks from the Glossary of Linguistic Terms (LinguaLinks Library), from which this answer was drawn, available through SIL International.]
The structural features of a narrative discourse vary. Since structure implies a common formula, it is difficult to apply one formula to "narrative discourse" in general. Narrative and discourse are fairly broad terms. Narrative might be defined simply as story: a recounting of events; linear or non-linear, and it can take one of many forms; prose, poetry, speech, film, song, etc.
Discourse can also be broadly defined; communication/debate and discourse(s) often form subsets which correspond to certain disciplines such as the discourse of politics.
So, the structure of a narrative discourse does have a universality in that literature or, texts in general, are based upon a similar structure and vary to certain degrees. The basic structure is: introduction, conflict and resolution. And it can stray from this (non-linear) or get more specific from there. For example, there is a common structure to romantic comedies and sitcoms; so much so, that their artistic quality tends to be criticized because of their lack of originality in structure. And that's what structuralists and subsequently, post-structuralists are all about: originality comes from changes in structure; not necessarily in character, theme, etc.
When you get into theoretical realms like Feminism and Marxism (sometimes called meta-narratives), these "discourses" form new kinds of structure to literature/texts because they have political agendas. Thus, Marxist texts may have similar structure because their stories deal with the same issues; just as romantic comedies tend to do.