Duolingo is the educational application category like playing a game, so the students can also use its casually without pressure, and also easy to accept and absorb because of flexibility. This application aims to help and develop the language skills, therefore, by involving third semester students of Mining Engineering Faculty of Engineering, as the community service activity uses the Duolingo application as an electronic learning medium to improve their English vocabulary skills. This community service activity has been carried out using the observation and classroom action, so, the result is the students are directly trained to always remember about the word means through the questions given at each level by using several pictures, games and others. Students can also take advantages of internet technology, in this case the use of the Duolingo application for language learning activities, especially English which is more creative, interesting, innovative and they have to understand the concept of learning media and the functions of learning media so that this Duolingo application provides an increase in English vocabulary because of its methods and forms in its implementation.