The author considers the problem of stylistic functions of linguistic units in modern Russian prose works through analyzing phraseological units in the detectives of B. Akunin. The article presents the most frequent types of phraseological units (idioms, set phrases, proverbs, sayings, popular expressions and other types of clichéd utterances) as representation of a personal literary style of this author. The research results point to their stylistic variety with high literary, colloquial, low colloquial, and slang units among them. The major types of phraseological unit conversion are distinguished as a prove of the writer's personal style, including, complete deformation of a component composition of a set phrase, reduction of the lexical length of phraseological units (implication), distribution of any component composition of the unit (explication), combining two or more phraseological units into a single set expression (contamination), replacement of a component in the composition of phraseological units with words of general literary layers (lexical variation), etc. The stylistic functions of all phraseological units under study are interpreted as retro-representation of the language of a certain time period, stylistic imitation of the communicative tone of oral speech, verbal characteristics of the characters who are referred to various social groups, and creation of humorous tone of the story. A comprehensive description of phraseological units used in modern fiction has revealed their artistic and stylistic potential.