In view of the traditional teaching mode, this study focuses on the application of big data in personalized English teaching in colleges and universities. It aims at improving the teaching effect by using big data. By combining personalized teaching and big data theory, this paper analyzes the current situation of college English teaching, clarifies the differences between students' needs and the advantages of big data, and puts forward teaching strategies based on big data, including personalized curriculum design, intelligent learning path planning, differentiated classroom teaching, and accurate evaluation feedback. From the analysis of practical cases in many universities, it is clear that the application of big data has achieved remarkable results.