The consonant system in the letters of serdars and gubernators Radonjic contain all sonant and obstruent that today literary language has. However, there aren’t particular graphic signs which would be adequate to denote specific consonants, and that fact designates the imperfection of the graphic system. Occurrence of soft consonants /ś/ and /ź/ as well as affricate /dz/ that still exist in today's speech of Njegusi (Ivic, Petrovic 1981:539 ) cannot be disputed even graphic differentiation is missing for /s/ and /ś/ (/sj/ > / ś / ), /z/ and /ź/ (/zj/ > /ź/), and probably for /dz/ and /c/, /dz/ and /z/, i.e. for /c/. Imperfection of the graphic system for writing in 18th and the first three decades of 19th century is reflected in the terms of phoneme /dž/. There is not any special graphic character for phoneme /dž/ either (it marks with /ž/), but examples confirm its existence in the letters of Radonjici. Consonants /ś/ and /z/ that resulted from voice alternation (new and jekavian jotovanje), exist in Montenegrin and Hercegovian vernacular. These consonants belong to system of voices of modern Montenegrin language and still exist in Montenegrin vernacular. In old Montenegrin vernaculars as well as in other Montenegrin vernaculars, consonant group /–sj/ is changing and gives phonemes /ś/ while consonant group /-zj/ gives /z/. Presence of soft consonants /ś/ and /z/ in vernacular of Njegusi, birth place of serdars and gubernators Radonjic, has been confirmed in the researches of Pavle Ivic and Dragoljub Petrovic. Soft consonants (/ś/, /z/) in letters of Radonjic are not marked with any with special graphic characters, but soft consonant /s(ś)/ is marked with grapheme , and soft consonant /z/ is marked with two phonemes (with and =/đ/). Phoneme /dz/ is also found in the letters of Radonjic. It has been found in lexemes generals (/zenerao/) and office (/kanzalerija/), which are not marked with traditional grapheme , but with grapheme . Phoneme /dz/ is found in letters of bishops Visarion and Danilo, but they use tradition graphemes and sometimes . In letters of Radonjic as well as in the letters of bishops Visarion and Danilo it is about loanwords from Italian language, precisely Venetian dialect. DOI: 10.5901/mjss.2014.v5n13p0552