With the continuous development and application of big data technology, its potential and value in the field of education are gradually emerging, especially in oral English teaching, big data is placed on high hopes. However, the research on how to effectively use big data to improve the efficiency of oral English teaching is still in its infancy. This study aims to fill this research gap and explore and analyze how oral English teaching strategies based on big data can improve teaching efficiency through in-depth literature review and empirical research. The results show that big data can help teachers assess students’ oral ability more accurately, and significantly improve students’ oral expression ability and learning efficiency by optimizing teaching strategies. However, oral English teaching strategies based on big data also have certain limitations, which need further research and improvement. This study provides a powerful theoretical basis and practical guidance for promoting the application of big data in oral English teaching.