This doctoral thesis analyses in detail the phonological and morphological features of Buzet dialect. According to the generally accepted classification by Dalibor Brozović the Buzet dialect or the Northern Chakavian is one of six dialects of the Chakavian dialect. It is characterized by the pronoun kaj, and that is the main reason why many researchers have mistakenly classified it as a Kajkavian dialect. It covers the area around Buzet in northern Istria. Its easternmost point is Lanišće, the westernmost Rušnjak, the northernmost Brest, and the southernmost Pagubice. It is an indigenous dialect belonging to the north-western Chakavian dialects. It is characterized by a distinct differentiation, and this is best reflected in large differences in vocal systems between individual speeches. Main characteristics of this dialect are the following: all speeches have a common voice ẹ which has retained its phonological individuality and appears in the place of a shorter yat; the semivowel in short syllables with inconsistent reflection turns into as many as six vowels: a, e, ɛ, o, ọ and ų; reflection of the flock depends on the (un) emphasis; transition of longer o to u; vowels i, ẹ, e and ɛ as a result of the sequence -ьje; reflection of a in the creative morpheme -nǫ- in verbs of second category; equalizing N and A singular feminine nouns denoting what is inanimate in most speech; lack of vocal lengthening in front of sonant; the presence of neo circumflexes in certain e-presents and adjectives. Moreover, one of the peculiarities of these speeches is the contrast in vivacity in singular of feminine nouns. Namely, in G the singular of the mentioned nouns denoting what is alive the suffix coincides with A the singular of nouns belonging to the accent type A. Final -l at the beginning of the final syllable in nouns and at the beginning of the internal syllable in nouns and adjectives changes to ṷ, v or f while in southern dialects, this consonant is reduced in the verb adjective masculine singular. In some speeches, the reflections of o / ọ / u / ṷ are interesting. The old consonant group *čr is preserved in the whole dialect, and the result of the Common Slavic and Old Croatian group *skj, stj > skəj is šć. The Common Slavic consonant group *zdьj was transferred to žj in the declension of the noun daš, and in the lexeme meaning 'grapes' the group *zdьj (poslije *zdǝj) (> Old Croatian *zdəj) was metatised and rotated in jz. Moreover, the *dj group consistently switched to j in all speeches. As for the group *zdьj > zdǝj) which gave rise to the noun meaning 'brain', in part of the speech it changed to žj (< žlj), in the other part to žg, while only in the speech of Oslići is its reflection žd. Relating to the accent system, this dialect is divided into two large units: language with one-accent system and language with two-accent system. An important accent feature is lengthening in the unstressed penultimate syllables that are included in central, western, and north-western dialects. Other phonological and morphological features are: vocal closing and diphthonging; transition of the anterior nasal ę to a only behind the palatal j; transition of phonemes l to u (in most examples); delateralization; transition -m to -n at the end of a grammatical morpheme; rotacism; loss of consonant r in front of v in the consonant group as well as in the sequence with the syllabic r; interrogative and relative pronoun kateri meaning 'which'; omission of sibilarization as a morphological category; elision (loss of initial unstressed vocals); devoicing of final sound consonants; special forms of the verb ‘to be’ as for the formation of conditionals; t-declension in personal masculine nouns ending in -o and -e; truncated infinitive. The result of research justifies the fact that the present dialect should be considered as a separate dialect of the Chakavian dialect. Moreover, there are some linguistic features that appear in it and that are characteristic of the Slovene language due to their geographical proximity and historical contacts. However, this is not about the influence of one language to another, it is about dialectal continuum because Buzet dialect is located between Notranjska (Slovene) and northern Chakavian dialect so, it is logical they developed common linguistic features in their coexistence. Based on the entire material and its analysis, a classification into systems of lower dialectological rank - groups of speech - is offered. The initial classification criteria were: reflection of the inconsistent semivowel, vocal systems: inventory and distribution, reflection of the posterior nasal in root morphemes, reflection of the flock, accent systems and reflection of the final -l. Analysis of linguistic features showed that the Buzet dialect can be divided into as many as ten speech groups, which testifies its distinct differentiation. The Pagubice dialect – a settlement located in the extreme south of Buzet dialect, is partly close to the neighboring North Chakavian Ekavian dialect of Pazin type, and this is the reason why it is one of the so- called marginal speeches. Marginal features of this speech are as follows: the independent preposition va (<*vъ), certain number of ekavian dialect words, u as a reflection of the posterior nasal in most examples, pronoun kujȉ meaning 'which' and the transition v to f at the end of the word as well in front of voiceless consonants. These linguistic features are not known to other (or at least most) idioms of this dialect, but represent the characteristic of the North Chakavian Ekavian dialect, where Pagubice is the border.