The main aim of this study is to design English-Afaan Oromo bilingual machine readable dictionary using English WordNet. The availability of electronic documents in different languages and the dissemination of internet technologies over the world are inspiring researchers to investigate how to design efficient machine translation and cross language information retrieval systems. Since these systems plays a vital role by letting users to use their own language over the internet and electronic devices. Especially, if we are talking about translation it is must to have a good bilingual dictionary. So, English-Afaan Oromo machine readable bilingual dictionary is main components of both systems listed before.