Backgrounds: This study aims to describe the implementation of threelanguage literacy by literacy ambassadors in developing language literacy and increasing literacy interest in students at SD Negeri Nayu Barat 02. Methods: The method used in this study is qualitative with a case study design. Sources of data were collected by conducting observations, interviews, and documentation. While data analysis using an interactive analysis model includes the stages of data collection, data reduction, data presentation and conclusion. The data validity technique is technique triangulation and source triangulation. Results: The literacy program at SDN Nayu Bart 02 is carried out by literacy ambassadors. Literacy ambassadors are selected students from the class tasked with introducing three languages. Three-language literacy is implemented using the habituation method, the habituation method with greetings in three languages. This program can improve students' language literacy, improve excellent and correct language skills, develop students' independence and self-confidence as students who are creative, innovative, productive, and have character. Novelty: The role of literacy ambassadors is as an information exchange, modeling and reinforcement of peer norms and values and invites students to play an active role in library activities. In this study, there is one role of literacy ambassadors, namely as a modeling model who exemplifies the pronunciation of vocabulary correctly and adequately according to the speech introduced to his colleagues through three languages, namely Javanese, Indonesian, and English.