Speakers not always maintain all grammatical norms in oral speech. However, before the Internet came into being the written public speech was predominantly based on preservation of Armenian language norms, which was largely a subject to censorship and editing. Today the situation has dramatically changed. Alongside with numerous mistakes (spelling, punctuation, lexical), a great variety of cases regarding the violation of grammatical norms are evident. The given article is dedicated to the study of these cases. Particularly, the mistakes concerning the plural, the incorrect usage of dates, pronouns and link words, cases of violation of verbal norms, as well as penetration of some common expressions of everyday language into written speech have been considered.