The purpose of this paper is to explore the application of computer to foreign language learning in Big Data era. Combining the properties of language learning and teaching theories, we analyze the potential uses of computer in foreign language learning. We find that the main potential of computer-based foreign language learning lies in making authentic language resources accessible to learners, providing Big Data analysis for foreign language teaching and triggering the new online learning and teaching models. As for foreign language learning in Big Data era, we propose that the application of computer should be based on the learners’ need and teachers’ instruction.