Blogs adapted in online news media have become a tool that allows citizens to express their opinions about current affairs (McDougall, 2005). The aim of this study is to make an approach to aggressive language, doing a detailed view about the use of coprolalic expressions used by readers who comment on electronic newspaper blogs. There were analyzed 20 articles of two Chilean newspapers, El Mostrador y El Mercurio. The analysis of the corpus was made with the Appraisal Theory (Martin & Rose, 2003; Martin & White, 2005), considering specifically the Attitude Category. As a general result, it was found a highest incidence of aggressive expressions in comments of electronic newspaper blogs. The newspaper with the highest incidence of abusive language was El Mostrador which is less precise about the identification and participation of the users. Consequently, this issue will have an effect on the coprolaic language. In both newspapers, aggressions are associated to the Judgement subsystem, questioning the capacity of other users.