The dialect of Njeguši belongs to the Katunian speech group, which is part of the LovćenRumija group of Montenegrin Old Štokavian speeches. This dialect has a specific prestige in Montenegro because it is the native idiom of the rulers and bishops of the last Montenegrin dynasty – the Petrović dynasty (17th – 20th centuries), that left behind numerous texts of a literary, cultural and historiographical nature. Despite this, this is the first detailed description of this dialect, although the necessity of such a description has been emphasized for the sake of the highest quality presentation of the language of the given texts. Since villages of Njeguši are largely abandoned today, and the speech of the inhabitants is rapidly changing (due to emigration and increased mobility of the population, education, media, but also due to the fact that Njeguši have become a tourist center), finding authentic speakers is rather difficult. On the basis of the results of personal field research, transcripts of records from earlier field researches and older audio-recordings with relevant native speakers, this thesis provides a description of the phonology, morphology and syntax of Njeguši dialect, as well as elements of lexis. The description is synchronous. In the phonological part, the consonant, vowel and accent systems are described. Morphology covers all types of words. Accent typology is given through morphological paradigms. The morphological and phonological part were done to a certain extent on the basis of a specially created questionnaire. Notes on syntax are given based on spontaneous speech. Changes in speech have been diagnosed in records created in the last 50 years. They are largely result of the influence of the standard variety through education.