Hundred years ago after the death of big Vukovarian, Croatian and European Nikola Andrić (1867 – 1942) his work is still not analysed and valued properly. In Croatistics he is know because of his language adviser Branič jezika hrvatskoga (1911), but his work extends to all ways of Croatian cultural and scientific life from the end of 19th century and first half of 20th century (literature, linguistics, theatre, publishing). The purpose of this work was to describe Andrić’s linguistic work and give a detailed description of the language he wrote in. Andrić’s life, socio-political circumstances that reigned in Croatia, and situation in Croatian linguistics are all being described in the first part. In the second part his articles that have linguistic theme are analysed as well as all those in which he wrote about language. Branič jezika hrvatskoga and a graphic dictionary Šta je Šta are shown in very detail as two of his most important contributions to Croatian linguistics. The third part shows Andrić’s language described at the orthographic, spelling, phonological, morphological, syntactic and lexical level. The changes his language experienced during his 50-year-long prolific work are also shown. In conclusion, Andrić’s most important aspects about language issues are counted and characteristics of his language are pointed out. Nikola Andrić’s work is put in correlation with the views of then leading linguists Ivan Broz, Tomo Maretić, Vatroslav Jagić. His attitude towards Vuk Karadžić’s work is also examined. Finally, the overview from his point of view about relation of standard Croatian language and dialects, regionalisms and localisms is also given. His fight against loan – words, especially Serbian loan – words is highlighted. This work gives a whole overview of Nikola Andrić’s linguistic work and indicates his big contribution to development and conservation of Croatian language. It is shown that this big Vukovarian revolts and gets ahead of the views that “vukovci” had; he continues the copious Croatian linguistic tradition and follows the developmental way of Croatian language written in the works of old Croatian grammar writers. In that way, the work of Nikola Andrić has a big part in Croatian linguistics.