The classroom teaching mode combining the flipped classroom and the paired classroom can better emphasize the exchange of information between teaching and learning, learning and learning, and then solve the problems of students’ explanation, demonstration, and practice ability. This paper explores the English teaching process in public security colleges under the guidance of the new teaching mode on the basis of the flipped classroom and analyzes the applicability and feasibility of the flipped classroom to English teaching in public security colleges. In order to explore whether the English teaching mode of public security colleges under the flipped classroom can improve students’ English performance, this paper constructs an English teaching quality evaluation model for public security colleges under the flipped classroom by improving the BP neural network. Through the teaching experiment to explore the changes in students’ English performance, the English performance of the experimental class fluctuated greatly, with an average score rising from 60.563 to 77.582, which is an improvement of 28.1%. It shows that the effectiveness of English teaching is better in the flipped classroom teaching mode.