The article considers sound prolongations as one of the most typical hesita-tion phenomena of spontaneous spoken speech in any language. The materi-al for the analysis was 40 monologues-descriptions, partly taken from the corpus of Russian monologue speech “Balanced Annotated Text Library”, and partly recorded specifically for this study. The monologues were record-ed from 4 groups of speakers: 10 Russians and 30 Chinese, of whom 10 de-scribed the comic strip in Russian and Chinese, and another 10 only in Chi-nese. The analysis showed that the appearance of prolongations correlates with the language factor: bilinguals use them more often than monolinguals. More prolongations were found in full-fledged words (not pragmatic mark-ers), but most of them are function words and pronouns. In Russian speech, the percentage of prolongations is also high in pragmatic markers, especially in the word vot, which appears in spoken discourse most often as a hesitative boundary marker. Thus, it turned out that even language proficiency does not make the Russian colloquial speech of the Chinese as natural as one of the native speakers. Prolongations predominate in vowels and sonorants; they are frequent at the end of a word and in single-letter words. Often pro-longations become a component of an extended hesitation chain that in-cludes other hesitative units (physical hesitation pauses, breaks, repetitions, vocalizations, etc.). The data obtained can be useful in all aspects of applied linguistics: from linguodidactics and linguistic expertise to automatic speech processing systems and the creation of artificial intelligence.