As a Roman senator and close friend to Coriolanus, Menenius views himself as Coriolanus's mentor and advisor. He consistently urges Coriolanus to control his temper, appear humble before the people, and soften his harsh language. Menenius understands the importance of diplomacy and the power of gentle words. He also seeks to prevent a popular uprising, believing that "the violent fit o' the time" (III.ii.33) could lead to civil war unless Coriolanus responds to the accusations against him with respect. Menenius frequently uses conciliatory language, recognizing its value.

Menenius's recounting of "the fable of the belly" (I.i.96-163) aims to calm the angry citizens and persuade them to accept their subordinate role in society. Many commentators have noted the ambiguity of this speech. On the surface, it serves as an allegory for a well-ordered state, where each social group performs its assigned role, ensuring the welfare of the entire body politic. To some, it appears patronizing—a simplistic tale that Menenius interprets to serve his own interests. His reading suggests that the Roman aristocracy is determined to maintain the current social order and that the country will function with or without its common citizens. It may also imply that Menenius views the body politic solely in terms of physical needs and desires. A citizen in his audience points out that Menenius's retelling omits higher functions of the body: intellect, imagination, and benevolence.

Menenius enjoys presenting himself as a genial old man who loves eating, drinking, and storytelling. The tribunes see him as a charming, harmless fellow known for good-natured teasing. They fail to recognize the sincerity of his insults; when he calls them asses and hypocrites and mocks their official duties, they dismiss his remarks as the usual jokes of someone who doesn't take himself or others too seriously. However, others, including some citizens, sense a darker meaning in his jokes. In I.i, Menenius tries to downplay the shrewdness of a citizen's commentary on the fable of the belly by mocking the man as "the great toe" (I.i.155) of the body politic. His true opinion of the people becomes evident when he later refers to them as the rats of Rome.

By the end of the play, Menenius is a pitiable character. The Volscian guards ridicule his assertions that he is Coriolanus's closest friend and scorn his repeated efforts to convince them of his importance. Coriolanus dismisses him, refusing to heed any more of his counsel. This is precisely the kind of treatment Cominius had cautioned Menenius about if he ventured to the Volscian camp. Perhaps it speaks to his dedication that he endured such abuse and humiliation for the sake of Rome.